Clash of the terabyte titans: Crucial M500 960GB vs. Samsung 840 EVO 1TB

I feel a little silly saying this, but the Crucial M500 960GB and Samsung 840 EVO 1TB are two of the best values in the SSD market. Both drives sell for north of $500, which puts them firmly in high-end territory. However, they also have loads of storage. If you do the math, these terabyte flagships actually cost less per gigabyte than lower-capacity models with cheaper price tags. And they have higher performance ratings, too.

Considering the manufacturers, we probably shouldn’t be surprised that these drives are such relative bargains. Samsung is the largest producer of flash memory in the world, while Crucial is the consumer brand of memory giant Micron. Both firms have cutting-edge NAND fabrication facilities, and their SSD divisions are first in line for the latest chips. Those divisions no doubt get a nice family discount, too.

The question, of course, is which of these flash giants makes the best SSD? We’ve pitted the M500 960GB against the 840 EVO 1TB to find out. We’ve also included smaller variants from each lineup to provide a little extra flavor for folks with tighter budgets. Join us as we crown the king of the terabyte titans.

TLC vs. MLC flash

Since we’ve already covered lower-capacity versions of the Crucial M500 and Samsung 840 EVO in earlier reviews, we won’t rehash all the details here. I suggest reading those initial articles for a detailed look at each drive’s underlying architecture. Today, we’ll highlight a few key differences and similarities before moving on to the results of our exhaustive performance testing.

By far the biggest difference between the M500 and the 840 EVO is the flash memory under the hood. Like most consumer-grade SSDs, the M500 features MLC NAND with two bits per cell. The 840 EVO is based on TLC flash that squeezes an extra bit into every memory cell.

Flash cells represent data with a negative charge created by trapped electrons. Because there’s some unavoidable variation in the nanoscale characteristics of each cell, all data is verified after it’s written. The verification process takes longer with TLC NAND, which must differentiate between eight possible values between 000 and 111. MLC NAND only needs to worry about four values between 00 to 11.

Due to the more involved verification process, TLC NAND typically has slower write speeds than its MLC counterpart. However, the 840 EVO isn’t a typical TLC implementation. Although much of its flash has three bits per cell, a portion is addressed as server-style SLC NAND with only one bit per cell. This SLC zone totals 12GB and is reserved for TurboWrite, which caches incoming data to mitigate the slower write speeds associated with TLC flash. Cached data is held in the TurboWrite buffer until the EVO slips into an idle state, after which the data is passed along to main storage.

Model Max
sequential (MB/s)
Max 4KB random (IOps) Price $/GB
Read Write Read Write
Crucial
M500 240GB
500 250 72,000 60,000 $145 $0.60
Crucial
M500 480GB
500 400 80,000 80,000 $350 $0.73
Crucial
M500 960GB
500 400 80,000 80,000 $530 $0.55
Samsung
840 EVO 250GB
540 520/270 97,000 66,000 $165 $0.66
Samsung
840 EVO 500GB
540 520/420 98,000 90,000 $320 $0.64
Samsung
840 EVO 1TB
540 520/420 98,000 90,000 $570 $0.56

Thanks to TurboWrite, the 840 EVO 1TB has a peak sequential write speed of 520MB/s. Writes proceed directly to the TLC flash if the TurboWrite buffer is full, but that only drops the EVO’s sequential speed rating to 420MB/s—20MB/s higher than the M500’s peak write rate. At least according to the manufacturers’ specifications, the 840 EVO is faster than the M500 not only in every category, but also across the multiple capacities we’ve tested. In a moment, we’ll see if that dynamic holds up in the wide variety of benchmarks that make up our storage test suite.

Testing performance is easy enough, but measuring endurance is too time-consuming for a comparison like this one. That’s unfortunate, because write endurance is an important consideration given the contenders. As data is written to NAND, the individual memory cells degrade, shrinking the range of voltages that can be used to represent data. This shrinkage is more problematic for TLC flash, which must differentiate between more values within that narrowing window.

Samsung doesn’t publish an official endurance specification for the 840 EVO, but Crucial says the M500 can withstand 40GB of writes per day for five years, or 72TB total. Based on what we’ve seen in our ongoing SSD Endurance Experiment, Crucial’s estimate is a conservative one. Thus far, we’ve written over 400TB to a collection of MLC-based drives, and they’re all in excellent shape. I can count the number of bad blocks on one hand.

Our experiment doesn’t include the M500 or the 840 EVO. However, it does feature Samsung’s first-generation TLC drive, the 840 Series. That SSD showed its first bad blocks after 100TB of writes, and it’s accumulated over 1300 of ’em through 400TB of writes. We also encountered unrecoverable errors while performing a data retention test at the 300TB mark.

TLC NAND clearly isn’t as robust as the MLC alternative. That said, hundreds of terabytes is an awful lot of writes for a consumer-grade SSD. The drive in my primary desktop writes only about 2TB per year, so it would take me half a century just to get to 100TB.

SSDs employ advanced signal processing and error correction algorithms to make the most of their NAND’s limited lifespan. Crucial also endows the M500 with an extra layer of protection inherited from Micron’s enterprise-class products. Dubbed RAIN, this RAID-like redundancy scheme uses a portion of the flash to house parity information. If the user’s data is compromised by a physical flash failure, it can be reconstructed with the parity information stored on the drive.

The flash reserved for parity is inaccessible to the user, which explains the M500’s lower capacity. The drive actually has a terabyte of flash onboard. RAIN and overprovisioned spare area each take a slice, leaving only 894GB for the user.

Even though the 840 EVO doesn’t have to worry about parity data, its TurboWrite cache monopolizes some of the flash. With the same 1TB total NAND capacity as the M500, the EVO delivers 932GB to the user. The 38GB difference works out to only 4%, but that’s still enough to store a lot of applications and games—or one blockbuster title with high-resolution textures.

Similar specs

Despite their differences, the Crucial M500 960GB and Samsung 840 EVO 1TB have quite a lot in common. Their flash is built on similar fabrication technologies, for example. The EVO’s flash is fabbed on a 19-nm process, while the M500’s is made with 20-nm technology.

Also, both drives have 128Gb (16GB) NAND dies that double the capacity of the 64Gb (8GB) dies commonly found in other SSDs. These 128Gb dies are key to reaching terabyte territory. They’re also a liability for the lower-capacity models. The M500 240GB and 840 EVO 250GB use only 16 dies each, but 32 dies are required to take full advantage of the internal parallelism in their respective controller chips. That’s why those models have lower write performance ratings.

With 64 dies apiece, the 960GB and 1TB variants have more than enough flash to saturate their controllers. The M500 uses a Marvell 88SS9187 chip, while the EVO sports a proprietary Samsung MEX design. Both controllers have eight parallel NAND channels.

Crucial deploys the M500’s NAND across 16 physical packages, while Samsung squeezes the same capacity into just eight. The 840 EVO’s circuit board is smaller as a result, though the cases are the same size. Each one measures 7 mm thick, allowing the drives to slip into slimmer notebook bays.

Speaking of notebooks, the 840 EVO 1TB is also available in mSATA form. Crucial doesn’t have a bite-sized version of the M500 960GB, though. The M500’s mSATA and M.2 flavors top out at 480GB.

When Samsung introduced the 840 EVO mSATA, it released new firmware for the 2.5″ version. This revision enables support for the TCG/Opal and IEEE 1667 encryption standards required by eDrive, Microsoft’s hardware-accelerated BitLocker implementation for Windows 8. The Crucial M500 has supported eDrive since its debut, so the EVO is a little late to the party. In fact, its eDrive firmware was originally scheduled for September. Better late than never, though.

Accompanying software

Software may be a secondary concern for solid-state drives, but there’s a big difference between what comes with the M500 and 840 EVO. The M500 drive is a barebones affair. There’s no accompanying Windows utility, and cloning software is only available with an installation kit that’s sold separately.

Samsung’s Magician utility and data migration software can be downloaded by any 840 EVO owner. The cloning tool is designed specifically for migrating from larger mechanical drives; it allows some data to be transferred to secondary storage rather than the target SSD, which is almost always smaller than the source hard drive. Then there’s the Magician utility, which can download and apply firmware updates, optimize system settings, monitor drive health, and read SMART attributes, among other things.

I’m not sure I trust the Magician utility’s general health indicator—it’s been far too optimistic about the state of the 840 Series drive in our endurance experiment. However, I do like how the main interface displays the total number of bytes written. Users still have to dig into the SMART data to track the number of bad blocks, but at least that’s easily done with through the Magician utility.

Third-party software is required to get similar information out of the M500. Even then, it’s not that simple. Check out the SMART attributes exposed by Hard Disk Sentinel, the utility we’ve been using to monitor wear in our endurance experiment:

The reallocated sector count adds up the number of bad blocks. There are no attributes for tracking writes, though. One of those vendor-specific attributes can probably be translated to total bytes written, but I wouldn’t trust an unlabeled attribute, and I’m surprised that such important information is obfuscated in the first place.

TR reader Karol tipped me off about the fact that the M500 does tally the number of logical sectors written in its extended SMART device statistics. Those stats aren’t accessible with common utilities like HD Sentinel. However, they are available via Smartctl, a command-line tool included in the free Smartmontools package. Getting a bead on total writes shouldn’t be this difficult, but at least it’s possible.

Crucial should really develop a Windows utility with basic monitoring capabilities. An integrated firmware updater would be nice, too. Samsung’s Magician software displays a notification when new firmware is available, and it handles both downloading the update and installing it.

The Magician utility also has a feature called RAPID mode, which uses a slice of system memory as a high-speed drive cache. We took a closer look at RAPID mode in August, and the caching solution did improve performance in some benchmarks. However, it slowed the EVO in other tests, and we’re not crazy about writes being cached in volatile DRAM. Unless you’re looking to set benchmark records, we recommend keeping RAPID mode disabled. The EVO is fast enough without it.

Our testing methods

If you’re familiar with our testing methods and hardware, the rest of this page is filled with nerdy details you already know; feel free to skip ahead to the benchmark results. For the rest of you, we’ve summarized the essential characteristics of all the drives we’ve tested in the table below. In addition to the M500 960GB, we’ve tested 240 and 480GB models from the same family. We’ve also benched the 250 and 500GB 840 EVO alongside the 1TB variant.

Cache Flash controller NAND
Corsair Force Series GT
240GB
NA SandForce SF-2281 25nm Intel sync MLC
Corsair Neutron 240GB 256MB LAMD LM87800 25nm Micron sync MLC
Corsair Neutron GTX
240GB
256MB LAMD LM87800 26nm Toshiba Toggle MLC
Crucial M500 240GB 256MB Marvell 88SS9187 20nm Micron sync MLC
Crucial M500 480GB 512MB Marvell 88SS9187 20nm Micron sync MLC
Crucial M500 960GB 1GB Marvell 88SS9187 20nm Micron sync MLC
Intel 335 Series 240GB NA SandForce SF-2281 20nm Intel sync MLC
Intel 520 Series 240GB NA SandForce SF-2281 25nm Intel sync MLC
OCZ Vector 256GB 512MB Indilinx Barefoot 3 25nm Intel sync MLC
OCZ Vertex 4 256GB 512MB Indilinx Everest 2 25nm Micron sync MLC
OCZ Vertex 450 256GB 512MB Indilinx Barefoot 3 M10 20nm Intel sync MLC
SanDisk Extreme II 240GB 256MB Marvell 88SS9187 19nm SanDisk Toggle SLC/MLC
Samsung 830 Series 256GB 256MB Samsung MCX 27nm Samsung Toggle MLC
Samsung 840 Series 250GB 512MB Samsung MDX 21nm Samsung Toggle TLC
Samsung 840 EVO 250GB 256MB Samsung MEX 19nm Samsung Toggle
TLC
Samsung 840 EVO 500GB 512MB Samsung MEX 19nm Samsung Toggle
TLC
Samsung 840 EVO 1TB 1GB Samsung MEX 19nm Samsung Toggle
TLC
Samsung 840 Pro 256GB 512MB Samsung MDX 21nm Samsung Toggle MLC
Seagate 600 SSD 240GB 256MB LAMD LM87800 19nm Toshiba Toggle MLC
WD Caviar Black 1TB 64MB NA NA

Apart from the drives sharing the spotlight, our collection of results includes some of the most popular SSDs around. You can find full reviews of most of the drives in our storage section.

The solid-state crowd is augmented by a couple of mechanical contenders. From the old-school hard drive camp, we have WD’s Caviar Black 1TB. We’ve included Seagate’s Desktop SSHD 2TB, as well. The SSHD combines mechanical platters with 8GB of flash cache, but like the Caviar Black, it’s really not a direct competitor to the SSDs. Those drives are meant to provide additional context for our SSD results.

If you’ve made it this far, you’re probably the sort of detail-oriented person who appreciates naked circuit board shots. So, here are a couple of the M500 960GB and 840 EVO 1TB. You can see even larger versions of these and other images from the article in the image gallery at the bottom of the page.

We used the following system configuration for testing:

Processor Intel
Core i5-2500K 3.3GHz
CPU cooler
Thermaltake Frio
Motherboard
Asus P8P67 Deluxe
Bios revision 1850
Platform hub Intel P67
Express
Platform drivers INF update
9.2.0.1030

RST 10.6.0.1022

Memory size 8GB (2
DIMMs)
Memory type
Corsair Vengeance DDR3 SDRAM
at 1333MHz
Memory timings 9-9-9-24-1T
Audio Realtek
ALC892 with 2.62 drivers
Graphics
Asus EAH6670/DIS/1GD5 1GB
with Catalyst 11.7 drivers
Hard drives Seagate
Desktop SSHD 2TB with CC43 firmware

WD Caviar Black 1TB with 05.01D05 firmware

Corsair Force Series GT 240GB with 1.3.2 firmware

Corsair Neutron 240GB with M206 firmware

Corsair Neutron GTX 240GB with M206 firmware

Crucial M500 240GB with MU03 firmware

Crucial M500 480GB with MU03 firmware

Crucial M500 960GB with MU03 firmware

Intel 335 Series 240GB with 335s firmware

Intel 520 Series 240GB with 400i firmware

OCZ Vector 256GB with 10200000 firmware

OCZ Vector 150 256GB with 1.1 firmware

OCZ Vertex 450 256GB with 1.0 firmware

SanDisk Extreme II 240GB with R1131

Samsung 830 Series 256GB with CXM03B1Q firmware

Samsung 840 Series 250GB with DXT07B0Q firmware

Samsung 840 EVO 250GB with EXT0AB0Q firmware

Samsung 840 EVO 500GB with EXT0AB0Q firmware

Samsung 840 EVO 1TB with EXT0AB0Q firmware

Samsung 840 Pro Series 256GB with DXM04B0Q firmware

Seagate 600 SSD 240GB with B660 firmware

Power supply Corsair Professional Series Gold AX650W
OS Windows 7 Ultimate x64

Thanks to Asus for providing the systems’ motherboards and graphics cards, Intel for the CPUs, Corsair for the memory and PSUs, Thermaltake for the CPU coolers, and Western Digital for the Caviar Black 1TB system drives.

We used the following versions of our test applications:

Some further notes on our test methods:

  • To ensure consistent and repeatable results, the SSDs were secure-erased before almost every component of our test suite. Some of our tests then put the SSDs into a used state before the workload begins, which better exposes each drive’s long-term performance characteristics. In other tests, like DriveBench and FileBench, we induce a used state before testing. In all cases, the SSDs were in the same state before each test, ensuring an even playing field. The performance of mechanical hard drives is much more consistent between factory fresh and used states, so we skipped wiping the HDDs before each test—mechanical drives take forever to secure erase.

  • We run all our tests at least three times and report the median of the results. We’ve found IOMeter performance can fall off with SSDs after the first couple of runs, so we use five runs for solid-state drives and throw out the first two.

  • Steps have been taken to ensure that Sandy Bridge’s power-saving features don’t taint any of our results. All of the CPU’s low-power states have been disabled, effectively pegging the 2500K at 3.3GHz. Transitioning in and out of different power states can affect the performance of storage benchmarks, especially when dealing with short burst transfers.

The test systems’ Windows desktop was set at 1280×1024 in 32-bit color at a 75Hz screen refresh rate. Most of the tests and methods we employed are publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.

HD Tune — Transfer rates

HD Tune lets us present transfer rates in a couple of different ways. Using the benchmark’s “full test” setting gives us a good look at performance across the entire drive rather than extrapolating based on a handful of sample points. The full test gives us fodder for line graphs, which we’ve split up by drive maker. You can click the buttons below each line graph to see how the M500 960GB and 840 EVO 1TB compare to their rivals.


To make the bar graphs easier to read, we’ve highlighted the M500 and 840 EVO families in different colors. We’ve also marked the terabyte-class models with brighter shades.

The 840 EVO 1TB gets off to a good start, just edging out the M500 960GB in HD Tune’s sequential read speed test. The difference between the two drives is slim, and the rest of the M500 and 840 EVO models deliver comparable performance.


HD Tune’s sequential write speed test produces some funky results with the M500. Flipping through the line graphs reveals similar behavior from several of the other SSDs, and it seems to be unique to this particular test. The M500’s average write speed suffers as a result, causing the drive to fall well behind the 840 EVO.

Check out the line graph for the Samsung SSDs, and pay particular attention to the far left side of the plot. All the EVOs exhibit an early surge in write speeds thanks to their TurboWrite caches. The 1TB model has the largest buffer of the bunch, so its surge lasts the longest.

Also, note how the 840 EVO 250GB’s write speed falls dramatically after the initial TurboWrite boost. Remember what I said about 128Gb NAND dies being a liability for lower-capacity SSDs? That’s the first evidence.

HD Tune runs on unpartitioned drives, with no file system in place, which probably explains the write-rate spikes exhibited by some of the SSDs. For another take on sequential speed, we’ll turn to CrystalDiskMark, which runs on partitioned drives. We used the benchmark’s sequential test with the default 1GB transfer size and randomized data.

Here, the 840 EVO family has a bigger edge in sequential read performance. It’s faster than the M500 with writes, too, but by a much smaller margin than in HD Tune.

The M500 960GB and 840 EVO 1TB largely match the performance of the other models in their respective families. However, the M500 240GB has a much slower write speed than not only its siblings, but also the 840 EVO 250GB. The EVO’s TurboWrite cache probably deserves some of the credit for keeping the 250GB model competitive.

HD Tune — Random access times

In addition to letting us test transfer rates, HD Tune can measure random access times. We’ve tested with four transfer sizes and presented all the results in a series of line graphs. We’ve also busted out the 4KB and 1MB transfers sizes into bar graphs that should be easier to read without the presence of the mechanical drives throwing off the scale.

As before, click the buttons below the line graphs to compare the M500 960GB and 840 EVO 1TB to different groups of drives.


The SSDs all have similar random read access times. The M500 is a smidgen quicker in the 4KB test, but the difference is only four microseconds. I wouldn’t worry about it.

There is, of course, a much bigger difference between the access times of the SSDs and our lone hard drive. The Caviar Black is at least an order of magnitude slower, if not more. Seagate’s Desktop SSHD hybrid is much more competitive, but it can’t keep up with the SSDs as the transfer size increases.


Although the SSDs are closely matched in HD Tune’s 4KB random write test, the field spreads out in the 1MB test. There, the 840 EVO 1TB has a modest lead over the M500 960GB. All the EVOs perform almost identically, but the M500 240GB lags well behind its higher-capacity siblings.

Again, the largest deltas are between the solid-state and mechanical drives. The Caviar Black fares a little better than it did with reads, but the Desktop SSHD falls behind the SSDs even with the smaller transfer sizes.

TR FileBench — Real-world copy speeds

Concocted by resident developer Bruno “morphine” Ferreira, FileBench runs through a series of file copy operations using Windows 7’s xcopy command. Using xcopy produces nearly identical copy speeds to dragging and dropping files using the Windows GUI, so our results should be representative of typical real-world performance. We tested using the following five file sets—note the differences in average file sizes and their compressibility. We evaluated the compressibility of each file set by comparing its size before and after being run through 7-Zip’s “ultra” compression scheme.

Number of files Average file size Total size Compressibility
Movie 6 701MB 4.1GB 0.5%
RAW 101 23.6MB 2.32GB 3.2%
MP3 549 6.48MB 3.47GB 0.5%
TR 26,767 64.6KB 1.7GB 53%
Mozilla 22,696 39.4KB 923MB 91%

The names of most of the file sets are self-explanatory. The Mozilla set is made up of all the files necessary to compile the browser, while the TR set includes years worth of the images, HTML files, and spreadsheets behind my reviews. Those two sets contain much larger numbers of smaller files than the other three. They’re also the most amenable to compression.

To get a sense of how aggressively each SSD reclaims flash pages tagged by the TRIM command, we run FileBench with the solid-state drives in two states. We first test the SSDs in a fresh state after a secure erase. They’re then subjected to a 30-minute IOMeter workload, generating a tortured used state ahead of another batch of copy tests. Let’s start with the fresh-state results.

In each and every test, the 840 EVO 1TB comes out ahead of the M500 960GB. The Samsung drive only has a narrow lead in the Mozilla and TR tests, but the gap widens when the drives are copying larger files.

Interestingly, the 840 EVO 1TB is slower than the 500GB model in several tests. The 250GB model is slower still, but it doesn’t lag behind its brethren as much as the M500 240GB. Of course, even the low-capacity Crucial offering is much faster than the mechanical drives. It also has an edge over the Samsung 840 Series, which was replaced by the 840 EVO.

The M500 960GB and 840 EVO 1TB perform similarly in our simulated used state. It’s been a while since we’ve seen an SSD turn in substantially slower used-state copy speeds, but the last time was with the 840 Pro, and other Samsung SSDs have exhibited problems in the past. Fortunately, there are no issues with the EVO.

TR DriveBench 1.0 — Disk-intensive multitasking

TR DriveBench allows us to record the individual IO requests associated with a Windows session and then play those results back as fast as possible on different drives. We’ve used this app to create a set of multitasking workloads that combine common desktop tasks with disk-intensive background operations like compiling code, copying files, downloading via BitTorrent, transcoding video, and scanning for viruses. The individual workloads are explained in more detail here.

Below, you’ll find an overall average followed by scores for each of our individual workloads. The overall score is an average of the mean performance score for each multitasking workload.

Though its margin of victory is narrow, the 840 EVO 1TB comes out just ahead of the M500 960GB in DriveBench 1.0 overall. Let’s see what we can learn from the individual test results.

The lower-capacity M500 and 840 EVO models seem to struggle a little in the file copy test, but they’re not that much slower than their terabyte-class kin.

Once again, the hybrid and hard drive are both decimated by the solid-state field.

TR DriveBench 2.0 — More disk-intensive multitasking

As much as we like DriveBench 1.0’s individual workloads, the traces cover only slices of disk activity. Because we fire the recorded I/Os at the disks as fast as possible, solid-state drives also have no downtime during which to engage background garbage collection or other optimization algorithms. DriveBench 2.0 addresses both of those issues with a much larger trace that spans two weeks of typical desktop activity peppered with multitasking loads similar to those in DriveBench 1.0. We’ve also adjusted our testing methods to give solid-state drives enough idle time to tidy up after themselves. More details on DriveBench 2.0 are available on this page of our last major SSD round-up.

Instead of looking at a raw IOps rate, we’re going to switch gears and explore service times—the amount of time it takes drives to complete an I/O request. We’ll start with an overall mean service time before slicing and dicing the results.

The M500 960GB and 840 EVO 1TB may not have the lowest mean service times in DriveBench 2.0, but they’re pretty close to each other, and they’re not too far off the fastest SSDs we’ve tested. The 480 and 500GB variants are a little slower, while the 240 and 250GB models lag further behind. We can look at the read and write service times separately to get a better sense of what’s going on.

Interesting. The M500 960GB has a slight advantage over the 840 EVO 1TB with writes, but it’s a little slower with reads.

The read results are pretty close both within the M500 and 840 EVO families and for the SSDs at large. Writes are a different story, however. The field is more spread out, the lower-capacity M500 and 840 EVO models have higher mean service times, and the M500 240GB even trails the mechanical drives.

Note that the M500 240GB and 840 EVO 250GB have much slower write service times than the other SSDs, most of which have similar capacities. Those other drives sport smaller 64Gb NAND dies, so they can take advantage of more controller-level parallelism at lower capacities. With 128Gb dies, the M500 and 840 EVO use half as many memory chips as their peers.

There are millions of I/O requests in this trace, so we can’t easily graph service times to look at the variance. However, our analysis tools do report the standard deviation, which gives us a sense of how much service times vary from the mean.

Greater variance isn’t necessarily a problem if service times are low overall, as they are with DriveBench read requests. However, the M500 240GB has longer write service times and more variance among them. That isn’t an attractive combo, especially since the 840 EVO 250GB fares better according to both metrics.

The M500 960GB has more variance in its write performance than the 840 EVO 1TB, but since the mean service times are low for both drives, I wouldn’t worry too much about the discrepancy.

We can’t easily graph all the service times recorded by DriveBench 2.0, but we can sort them. The graphs below plot the percentage of service times that fall below various thresholds. Once again, the buttons below each graph switch between different sets of drives.



The mechanical drives are the only ones that deviate substantially from the curves followed by the SSDs. They have fewer service times under each threshold, at least until we hit 100 milliseconds.

We’re particularly interested in service times beyond 100 ms, since those could be long enough for users to notice. The following graphs tally the number of extremely long service times exhibited by each drive in DriveBench 2.0.

The 840 EVO 1TB has fewer 100+ ms service times than the M500 960GB with both reads and writes. In fact, all of the EVOs come out ahead of their M500 competition. The most worrying results are produced by the M500 240GB, which has nearly 15 times more extremely long service times than its 960GB counterpart. Ouch.

IOMeter

Our IOMeter workloads feature a ramping number of concurrent I/O requests. Most desktop systems will only have a few requests in flight at any given time (87% of DriveBench 2.0 requests have a queue depth of four or less). We’ve extended our scaling up to 32 concurrent requests to reach the depth of the Native Command Queuing pipeline associated with the Serial ATA specification. Ramping up the number of requests also gives us a sense of how the drives might perform in more demanding enterprise environments.

We run our IOMeter tests using the fully randomized data pattern, which presents a particular challenge for SandForce’s write compression scheme. We’d rather measure SSD performance in this worst-case scenario than using easily compressible data.

There’s too much data to show clearly on a single graph for each access pattern, so we’ve once again split the results by drive maker. You can compare the performance of the M500 960GB and 840 EVO 1TB to that of the competition by clicking the buttons below each graph.


The web server access pattern is comprised entirely of read requests, and the 840 EVO 1TB has a clear advantage over the M500 960GB. The various M500 and 840 EVO capacities perform similarly here. While the EVOs have some of the highest I/O rates of the bunch, the M500s are less competitive, especially under heavier loads.




Our remaining IOMeter tests mix reads and writes, and this time, the M500 960GB trumps the 840 EVO 1TB—at least until the load really ramps up. The M500 hits its stride earlier and starts to plateau after eight concurrent I/O requests. The EVO starts slower, but its performance continues to scale through 32 simultaneous requests.

As one might expect given the results we’ve seen thus far, the lower-capacity M500 and 840 EVO drives are slower than the flagship models. The differences are relatively small compared to the gaps between those families and the fastest SSDs, though. The LAMD-based Corsair Neutron and Seagate 600 SSDs offer much better performance in these tests, and OCZ’s new Vector 150 delivers even higher I/O rates. You can blame the Vector for throwing off the scale for all the other drives.

Boot duration

Before timing a couple of real-world applications, we first have to load the OS. We can measure how long that takes by checking the Windows 7 boot duration using the operating system’s performance-monitoring tools. This is actually the first test in which we’re booting Windows off each drive; up until this point, our testing has been hosted by an OS housed on a separate system drive.

Level load times

Modern games lack built-in timing tests to measure level loads, so we busted out a stopwatch with a couple of reasonably recent titles.

No more than a second separates the fastest SSDs from the slowest ones in our load time tests. The 840 EVO 1TB technically comes out ahead of the M500 960GB, but the difference between those contenders is less than half a second. Yeah, you’re not going to notice that.

You will, however, notice the difference in load times between a solid-state and mechanical drive. The Caviar Black is much slower than all of the SSDs. The Desktop SSHD almost eliminates the gap, but its hybrid design can only accelerate access to data that users load frequently. SSDs provide wicked-fast load times regardless.

Power consumption

We tested power consumption under load with IOMeter’s workstation access pattern chewing through 32 concurrent I/O requests. Idle power consumption was probed one minute after processing Windows 7’s idle tasks on an empty desktop.

The M500 960GB sips a little less power than the 840 EVO 1TB at idle but slightly more under load. The lower-capacity drives in each family are more power-efficient, but the deltas amount to only one watt or less. Considering their capacities, the M500 960GB and 840 EVO 1TB draw relatively little power.

Conclusions

We’ve waded through a lot of performance data, and we’ll indulge a couple more graphs before weighing in with our final verdict. The following scatter plots use an overall performance score derived by comparing how each drive stacks up against a common baseline. This score is based on a subset of our performance data described here, and we’ve mashed it up with per-gigabyte prices from Neweegg. The best solutions are found in the upper left corner of the plot, which signifies high performance and low pricing.

Solid-state and mechanical storage have vastly different performance and pricing, and those disparities make the main plot a little busy. Click the buttons below the plot to switch between all the drives and a cropped look at just the SSDs—and keep in mind that we’ve trimmed the axes for the SSD-only plot.


The Crucial M500 960GB sells for $530, while the Samsung 840 EVO 1TB rings in at $570. Those prices put the drives on nearly equal footing on the price-per-gigabyte axis, but the EVO is faster overall. The EVO also maintains its performance advantage at lower capacities, and its 250GB incarnation is way ahead of the M500 240GB.

Samsung 840 EVO 1TB
December 2013

Zooming in on the SSDs reveals a lot of drives with comparable performance to the terabyte titans. Notice that none of those alternatives has a lower cost per gigabyte, making the flagship drives relative bargains.

There are considerations beyond where these drives fall on our value plots, of course. The M500 has built-in redundancy, and its two-bit MLC NAND should be more durable than the three-bit TLC flash in the 840 EVO. As we’ve learned in our endurance experiment, though, Samsung’s first-gen TLC drive can withstand hundreds of terabytes of writes without failure. The 840 EVO should last for years under typical client workloads.

Samsung bolsters the EVO with a strong software suite that includes a handy cloning tool and Windows utility. Those might seem like small additions, but they go a long way toward making the EVO feel like a complete package. Crucial doesn’t bundle any software with the M500, and the firm makes monitoring more difficult by masking the drive’s SMART attributes.

If you’re looking for a king-sized SSD to put inside a typical desktop or notebook, the Samsung 840 EVO 1TB is the better all-around option. It performs better overall, offers a slightly higher capacity, and comes with software that improves the user experience. The M500 960GB is an excellent drive, too, and it has my enthusiastic recommendation. But the M500’s strengths seem better suited to write-heavy workloads and entry-level enterprise applications. The 840 EVO 1TB is the more cohesive consumer product, and that’s why it’s our Editor’s Choice.

Comments closed
    • GeneMosher
    • 6 years ago

    Samsung’s EVO RAM is also available in the mSATA (Mini SATA) format.

    • gamoniac
    • 6 years ago

    Having just bought a Seagate 600 240GB a few weeks ago, I naturally paid it closer attention. And looking at the charts, I feel vindicated. On page 8, both performance and service mean time are quite remarkable, especially in the 240GB-512GB category. If Crucial M500 and Samsung EVO made it to the recommendation list, so should Seagate 600 IMO, especially because the price is far below what is on the performance-price scatter plot.

    * The price of Seagate 600 240GB is only $156 on Amazon, which comes out to be $0.61 – to $0.65 (depending on whether you count it is 240 or 256GB).

      • MadManOriginal
      • 6 years ago

      The Seagate drive is definitely a good all-arounder. I was tempted by a few deals on it (although I didn’t see the $90 after MIR Tigerdirect deal I’ve read about? I would have bit if I saw that) but when reading reviews for read performance, I am fine with the performance of my Intel 330 240GB which I got for <$120 a year ago.

    • davidbowser
    • 6 years ago

    I would love to see Crucial cooperate with a “inside the second” type of review of their SSDs. They seem to have these crazy stadard deviations and excessive 100+ms latency issues and I wonder how much work has actually been put into figuring it out.

      • dme123
      • 6 years ago

      You actually notice these issues if you’re using the drive in a heavy IO environment too. It’s one of the issues that have caused me to forsake Crucial drives and has been a persistent problem across 3 generations now.

    • BIF
    • 6 years ago

    Well, it’s about time we started seeing bigger SSDs. Vendors bring it on!

      • End User
      • 6 years ago

      I agree. I bought my M500 960GB back in April. Hopefully 1.5/2TB SSDs make an appearance in 2014.

    • Visigoth
    • 6 years ago

    The Crucial M500 960GB was available for $440 in the days leading to CyberMonday. Plus with MLC NAND, extra supercaps to flush any data from the buffer to NAND in case of a power failure, I say there’s a CLEAR winner for those who prefer the features I mentioned above. The only thing the Samsung has going for it are slightly faster speeds and good-looking software.

    As for me, I’ll take reliability over performance any day of the week.

      • albundy
      • 6 years ago

      was thinking about that one, but ended up going with 2 of the seagate 600 ssd 240gb for $90 each AR

      • stdRaichu
      • 6 years ago

      Yeah, I took basically the same decision when it was a toss-up between the two drives, and the price difference when I bought my M500 was much bigger than it is here – £350 for the M500 and £450 for the EVO. Since it’s a scratch drive for video editing, there’s very little difference in apparent speed and of course the MLC vs. TLC gives you a (possibly misguided) sense of the warm’n’fuzzies.

      IMHO, SSDs have been “good enough” in terms of performance for consumer use since about the third generation when the C300 came out, and it’s only those with more specialised applications that would notice the difference between 450MB/s and 500MB/s… and for those who really need crazy transfer speeds or especially IOPS, PCIe is where it’s at.

    • indeego
    • 6 years ago

    Anyone ever used one of these in a server environment? First, thank you for going first, secondly, how did it go? 🙂

      • davidbowser
      • 6 years ago

      Test Lab (non-prod) servers. I have also loaded Crucial SSDs in a NAS (RAID 0 and iSCSI) and it was pretty spectacular running VMs from it.

      If you read Storage Review they have reviewed the Micron M500 Enterprise SSDs, which are essentially the same as the Crucial ones, but with firmware tweaks. If you are building your own white box servers, I would test a few Crucial SSDs.

      • Scrotos
      • 6 years ago

      Not these models, but for consumer SSDs in a server environment, 8 x 256 GB 840 Pros in a RAID 1+0 SQL server. Working great so far. Limited by the older server they are in.

        • indeego
        • 6 years ago

        For SQL, is this vendor supported? Some databases do not support SSD implementations due to wonky flushing of cache that varies per SSD.

          • davidbowser
          • 6 years ago

          If the SSD is on a RAID card, the cache flushing should not be an issue, as it is handled by the RAID card. The down side is that you won’t get TRIM, so native SSD garbage collection is the most important thing.

          On that note, I would recommend focusing on the “dirty” scores for SSDs when considering using them for servers. If the IO profile for the workload is constant, the SSD may never have a chance to do anything more than firmware level garbage collection, even if TRIM is supported in a direct attached scenario.

            • jihadjoe
            • 6 years ago

            [quote<]I would recommend focusing on the "dirty" scores for SSDs when considering using them for servers.[/quote<] This is an interesting aspect of SSD performance that so far only Anandtech seems to have captured in a way that's easily digestible for readers (AFAIK). Thanks to their massive storage test rig, they have some pretty nifty charts showing sustained performance. Incidentally, Intel tends to do much better in those tests compared to other drives. Samsung's 840 Pro and Evo are currently the darlings of benchmarks, but they don't do nearly as well as Intel's 525 under sustained load. From their [url=http://www.anandtech.com/show/7555/mushkin-atlas-msata-240gb-480gb-review/2<]Mushkin Atlas review[/url<], some sustained performance charts for the 840 Evo. Initial performance is very high (and most sites will see only this aspect of the drive during benchmarking), but then falls off to about 5k IOPS. [url<]http://images.anandtech.com/reviews/storage/samsung/840EVO/250GB/1sm.png[/url<] Contrast with Intel's SSD 525, which pretty much maintains performance at or above the 50k IOPS level all throughout. [url<]http://images.anandtech.com/reviews/storage/intel/525/1sm.png[/url<]

      • ColeLT1
      • 6 years ago

      Not these drives, but I have been running a citrix xenapp environment virtualized (server 2008r2) on ESXI 5.1 for 1.5yrs, each server has a local samsung 830 256GB ( [url<]https://techreport.com/forums/viewtopic.php?f=33&t=83041[/url<] ). We started with around a 60 user load, but now it is up to 140 users and running great. 30% average CPU load during peak hours, and the users love how snappy all the programs are. I am currently building a new backupexec server but after that I will start to build out an ivy E5 with one of these 1TB SSD drives for the D.R. room, going to put 2 more 2008r2 citrix servers on it and mirror the profile server over to it hourly, I am leaning towards the crucial because there will be lots of writes going to this (vmware SDR/SRM).

        • davidbowser
        • 6 years ago

        disclaimer – I work for VMware. My opinions are my own.

        If you are already running local SSDs on your servers, take a look at VSAN. It might be a decent option for you when it comes out of beta.

          • ColeLT1
          • 6 years ago

          Thanks David, I will look into it, care to give me a quick overview of what it actually is and what it will do for me? The only thing on the SSDs are the 3 citrix servers plus a profile server.

          All 5 of my main servers are ISCSI-ed into a P6100s (all SSD) 9.6TB equalogic SAN. These 2 servers have the local SSDs for the low latancy and high performance needed for so many RDP sessions. I am on ESI 5.1 due to Backup exec 2010, I am building a haswell box for my new backupexec 2012 currently and will move to 5.5 soon.

            • davidbowser
            • 6 years ago

            If you are already using a SAN, the use case may not be ideal.

            [url<]http://www.vmware.com/products/virtual-san/[/url<] The short version is that it allows you to virtualize (abstract, pool) local direct attached storage so that ESX can use it as if it were a physical SAN. You are creating what amounts to a storage cluster across several servers so that if any single server storage fails, the data still lives (and VMs are still live). Just like RAID, you lose capacity in this scenario. It is still beta, so caveat emptor, even though you are not emaris (my Latin is weak) anything with beta software. The long term vision is to have all the bells and whistles that ESX has in a cluster (high availability, fault tolerance, dynamic resource scheduling, etc.) while being able to use commodity local storage. It IS NOT all things to all workloads, so I would not recommend running enterprise class stuff on this for another 18 months or so, and even then one would need to be careful.

            • ColeLT1
            • 6 years ago

            Thanks again David.

          • Deanjo
          • 6 years ago

          David, OT, why is Workstation nearly 5 times the price of Fusion?

      • dme123
      • 6 years ago

      I did this for 12 months for a database server with 4 x Samsung 830 in RAID10 and a hot spare. Worked great, no reliability issues. It was my intention to pull them after 12 months and replace with similar drives but now I can get Intel S3500 drives for a not dissimilar price I’ve just used those.

      For what it’s worth the 830s were still in good health and went on to serve in workstations. If you understand your workload and you’re willing to monitor them closely I see little reason not to do this.

      • Milo Burke
      • 6 years ago

      I put 3x Intel S3700 in RAID5 for our database server in March. It’s working well for us. Let me know if you want me to run a benchmark for you. =]

    • wierdo
    • 6 years ago

    Personally I prefer the 960GB M500 SSD, but I do agree that the 840EVO comes with pretty neat software.

    Performance is ridiculously good on both, so it’s hard at such levels to feel the (generally) minor differences between the two drives in actual use imho.

    But with the M500 there’s that peace of mind that comes from knowing you have MLC class chips under the hood, even if for most users the durability is more than good enough either way. I guess this is where it comes to personal preference.

    Great review guys, thanks!

    • Shambles
    • 6 years ago

    How quickly does the EVO move data from the SLC portion to the TLC? It’s not endurance I’m worried but data integrity during a power outage. Does it move the data to TLC within moments or does it sit on the SLC for quite some time trying to reduce wear to the TLC portions by reducing the amount of reads and writes? Having a file corrupted that’s in the middle of a transfer during a power outage is understandable but I don’t want to worry about every file I’ve touched in the last 30 minutes that might be sitting in cache waiting for a wear leveling algorithm before sending it to TLC.

      • sluggo
      • 6 years ago

      If the files are sitting in cache when the power goes down, they’ll be in cache when the power comes back up. It’s still non-volatile memory.

      If the files are being transferred from cache to TLC when the power goes down, you’re at risk. But you have the same risk when transferring data to HDD or a non-cache implementation of another SSD.

        • jihadjoe
        • 6 years ago

        +1 for your first point.

        As for the second, I imagine the they copy the data first and then move the pointers afterward, so it should be safe even if you lose power while the data is in transition from SLC to TLC.

    • Shambles
    • 6 years ago

    It says a lot when SSD manufacturers are putting more SLC flash on their drives to make up for TLC than HDD manufacturers are putting MLC on their SSHDs drives to make up for the archaic magnetic speeds.

      • indeego
      • 6 years ago

      optical?

        • Shambles
        • 6 years ago

        Derp, magnetic.

          • moose17145
          • 6 years ago

          mmmmm magnetic photons…

    • UnfriendlyFire
    • 6 years ago

    What about M500’s encryption chip? Or does Evo have one as well?

    (Sorry if I overlooked something. Sleep deprived.)

      • Dissonance
      • 6 years ago

      Both support the latest encryption standards. There’s a paragraph on the subject in the middle of page two.

    • ronch
    • 6 years ago

    I should really jump on the SSD bandwagon soon.

      • dragosmp
      • 6 years ago

      don’t, you’ll end up hating any rig that doesn’t have one

      • trieste1s
      • 6 years ago

      Once you do that, HDDs will forever be backup storage or media storage drives in your mind.

        • jihadjoe
        • 6 years ago

        That line of thinking has actually saved me quite a bunch on my mechanical storage purchases. Whereas before I was like “7200 RPM or bust!”, these days I only ever get 5.xk RPM HDDs.

    • ronch
    • 6 years ago

    Drive manufacturers should just agree that 1GB = 1,000,000,000 bytes. As it is, the way they advertise and label drives is akin to how CRT monitors had less actual viewable areas than what their manufacturers say on the box, like how a monitor that’s supposed to be a 17-incher only gives you 16″ of diagonal screen real estate. WTF.

      • Zizy
      • 6 years ago

      They do 🙂 Only ram and Windows remain on 2^10 instead of 10^3.
      Wish we moved to hexa system. But given some backwards countries havent even fully moved to metric I dont think I will ever see that happen.

        • Wirko
        • 6 years ago

        You got it backwards. The US still haven’t moved *from* hexadecimal. I heard that they cut inches in quarters and sixteenths, have 0x10 ounces in a pound, and can therefore measure pressure in ounces per square quarter of an inch.

        [url<]http://answers.yahoo.com/question/index?qid=20090116153528AAKEBwq[/url<]

        • Shambles
        • 6 years ago

        I believe you mean a gigabyte is 10^9 bytes not 10^3. 🙂

    • crystall
    • 6 years ago

    It seems that Samsung really did a great job at making the 840 series an excellent performer even when using TLC flash. I didn’t expect such a large difference between the two drives, the 840 is also surprisingly consistent. Personally I would still go for an M500 but mostly because of non-performance differentiators: namely power-loss protection and the inherently longer life-span of the MLC flash dies.

      • amagus
      • 6 years ago

      I recently chose the M500 over the EVO as the longevity issue worried me more than the speed differences. It helped that the best Black Friday deals had the 960GB M500 at $100 cheaper than the 1TB EVO.

      I plan on using it as a working data set drive for RAW video footage (which is enormous in size) from a cinema camera, so I’m going to be cycling through the bits at a much faster rate than a typical read heavy OS/app drive. I think there are a handful of use cases like this where longevity trumps speed. The M500 also is still plenty fast despite losing in the benchmark tests.

    • Wirko
    • 6 years ago

    [quote<]leaving only 894GB for the user[/quote<] [quote<]delivers 932GB to the user[/quote<] Is it a coincidence that 960,000,000,000 B = 894 GiB and 1,000,000,000,000 B = 931 GiB? I hate those geekbytes as much as the next guy but it should be clearly stated that you use these here. Using the manufacturers' (decimal) definition, a 1 TB or 960 GB drive has as much free space for user data as it's written on it.

      • Orwell
      • 6 years ago

      Wish I could give a million upvotes.

    • MadManOriginal
    • 6 years ago

    This feels like the first time in a while that the highest capacity of a storage medium doesn’t have a disproportionately high price/GB…interestly, but still more than I’d want to spend in absolute terms if only because I don’t ‘need’ this much fast storage. Could be nice in a laptop though.

      • Airmantharp
      • 6 years ago

      As shown in the charts, being a fast or slow SSD doesn’t really make much difference in boot times or application/game load times, but they sure do help when doing real work. In my case, it’s Lightroom, and yeah, this would be [i<][b<]really[/b<][/i<] nice to have.

        • travbrad
        • 6 years ago

        Yep if you are just using your SSD as a boot/application drive the performance differences between various SSDs really won’t be noticeable at all, and they are all dramatically faster than regular mechanical HDDs.

        If you need almost 1TB of solid state storage chances are you are doing more with your drive than just the OS/applications though, so the performance differences do actually matter.

          • moose17145
          • 6 years ago

          Not entirely true about needing a TB of storage and using your laptop / desktop for actual work. As was mentioned, having a SSD this big in a laptop would be extremely nice. I do not use my laptop for actual work outside of mainly word processing and maybe netbeans (which OMG does having a SSD make that program sooo much nicer to use), but my laptop also goes with me on all my army adventures, so having a lot of internal storage would be nice so that I do not need to always port a external with me while still having the benefits of a SSD for loading programs and overall system responsiveness. I know having an external isn’t a huge deal, but it would be nice to be able to carry fewer things with me and be able to store more / all of the things I want internally. Currently I only have a 128GB Crucial M4 in my laptop, so internal storage is very tight when you wanna bring some music and movies with you for down time entertainment. If i got one of these It would probably end up in my laptop and I would move the 128 M4 into my desktop as its primary boot drive where I have various secondary hard drives with multiple TB of storage. My desktop does not yet have a SSD since it stays turned on 24/7, so boot times are not really a huge concern.

            • MadManOriginal
            • 6 years ago

            Depending on the data stored, an SDXC card is an option if the laptop has a slot for it. 128GB SDXC cards aren’t terribly expensive, although getting the extra space over a ~120GB SSD in the form of a ~240GB SSD would make more sense.

      • ronch
      • 6 years ago

      Personally, I think 240GB is overkill for a C drive. I say, a 120GB SSD for drive C and a 2TB mech HDD for drive D.

        • dragosmp
        • 6 years ago

        there’s a case to make that if you use an SSD and you have to access with any kind of speed anything but an SSD you’ll be annoyed. On a 120GB drive you end up juggling which games you want to load fast and which can be slow, you need to trim documents folder… It can get complicated and a 240GB is slightly faster and cheaper per GB.

          • wrevilo
          • 6 years ago

          I like having 3 drives: 1 for Windows and the usual programmes, one for games and one for media.

          • travbrad
          • 6 years ago

          Yep 120/128GB is cutting it pretty close if you play a lot of games. The average game nowadays is 10-15GB, and some are 30GB.

          If you just installed Windows, BF3, BF4, and Max Payne 3 your drive would almost be full.

        • OmarCCX
        • 6 years ago

        I dual boot my 256gb so I split it, 80 / 170. I like to keep my music on the SSD, iTunes feels slow as shit when I put my 80gb library on an HDD.

          • travbrad
          • 6 years ago

          I think that’s probably a problem with iTunes rather than your HDD. iTunes has always felt slow to me. Winamp/Mediamonkey feel faster on my mobile Pentium 4 laptop with 512MB of memory than iTunes does on a i5-2500K, 8GB machine.

            • Visigoth
            • 6 years ago

            Yeah, iTunes is a piece of sh*t compared to those. You could also try AIMP, which is one of the best music players out there (using the BASS libraries for playback)

            [url<]http://aimp.ru/index.php[/url<]

        • Firestarter
        • 6 years ago

        With steam on my 256gb ssd, I’m feeling decidedly cramped. Whether you think such an SSD is overkill or not depends entirely on how you plan to use it and what the cost is that you have to incur. In my opinion, there is no overkill in SSD storage capacity, if I could’ve bought a 2 terabyte SSD for the same money I definitely would have.

      • Disco
      • 6 years ago

      I really like the idea of one of these drives for my laptop, where everything needs to be on the one single drive. I do plan on getting one eventually, but I can’t really justify spending almost as much on the SSD as I did on the laptop.

      Waiting until prices on these drop below $400. Maybe by next summer? Fall?

        • MadManOriginal
        • 6 years ago

        A significant price drop isn’t likely until the next flash process node shrink, and I’m not really sure when to expect that. Basic advancements like that in silicon manufacturing have been slowing down as the nodes shrink more, it used to be we could expect a shrink and the accompanying doubling of GB/$ once a year, but now we are over a year and a half from the last improvement in that metric.

Pin It on Pinterest

Share This