SSDs have come a long way since Intel released its first, the X25-M, a little more than four years ago. That drive was a revelation, but it wasn’t universally faster than the mechanical hard drives of the era. The X25-M was also horrendously expensive; it cost nearly $600 yet offered just 80GB of capacity, which works out to about $7.50 per gigabyte.
My, how things have changed.
Solid-state drives gotten a lot faster in the last few years. They’re already pushing up against the throughput ceiling of the 6Gbps Serial ATA interface, leaving mechanical hard drives in the dust. I can’t remember the last time we saw an HDD score better than an SSD in one of our performance tests.
More importantly, SSDs have become a lot more affordable. Today, you can get 80GB by spending $100. The sweet spot in the market is the 240-256GB range, where SSDs can be had for around $200—less than a dollar per gigabyte. Rabid competition between drive makers deserves some credit for falling prices, particularly in recent years. Moore’s Law is the real driving factor behind the trend, though. The X25-M’s NAND chips were built using a 50-nm process, while the new Intel 335 Series uses flash fabricated on a much smaller 20-nm process.
Designed for enthusiasts and DIY system builders, the 335 Series is aimed squarely at the sweet spot in the market with a 240GB model priced at $184. That’s just 77 cents per gig, a tenfold reduction in cost in just four years. The price is right, but what about the performance? We’ve run Intel’s latest through our usual gauntlet of tests to see how it stacks up against the most popular SSDs around.
Intel and Micron have been jointly manufacturing flash memory since 2006 under the name IM Flash Technologies. The pair started with 72-nm NAND flash before moving on to the 50-nm chips used in the X25-M. The next fabrication node was 34 nm, which produced the chips used in the second-generation X25-M and the Intel 510 Series. 25-nm NAND found its way into the third-gen X25-M, otherwise known as the 320 Series, in addition to the 330 and 520 Series. Now, the Intel 335 Series has become the first SSD to use IMFT’s 20-nm MLC NAND.
Building NAND on finer fabrication nodes allows more transistors to be squeezed into the same unit area. In addition to accommodating more dies per wafer, this shrinkage can allow more capacity per die. The 34-nm NAND used in the Intel 510 Series offered 4GB per die, with each die measuring 172 mm². When IMFT moved to 25-nm production for the 320 Series, the per-die capacity doubled to 8GB, while the die size shrunk slightly to 167 mm².
The Intel 335 Series’ 20-nm NAND crams 8GB onto a die measuring just 118 mm². That’s not the doubling of bit density we enjoyed in the last transition, but it still amounts to a 29% reduction in die size for the same capacity. Based on how those dies fit onto each wafer, Intel says 20-nm production increases the “gigabyte capacity” of its flash fabs by approximately 50%. IMFT has been mass-producing these chips since December of last year.
As NAND processes shrink, the individual cells holding 1s and 0s get closer together. Closer proximity can increase the interference between the cells, which can degrade both the performance and the endurance of the NAND. Intel’s solution to this problem is a planar cell structure with a floating, high-k/metal gate stack. This advanced cell design is purportedly the first of its kind in the flash industry, and Intel claims it delivers performance and reliability comparable to IMFT’s 25-nm NAND. Indeed, Intel’s performance and endurance specifications for the 335 Series 240GB exactly match those of its 25-nm sibling in the 330 Series.
Intel says the 335 Series 240GB can push sequential read and write speeds of 500 and 450MB/s, respectively. 4KB random read/write IOps are pegged at 42,000/52,000. Thanks to the lower power consumption of its 20-nm flash, the new drive should be able to hit those targets while consuming less power than its predecessor. The 335 Series is rated for power consumption of 275 mW at idle and 350 mW when active, less than half the 600/850 mW ratings of its 25-nm counterpart.
On the endurance front, Intel’s new hotness can supposedly withstand 20GB of writes per day for three years, just like the 330 Series. As one might expect, the drive is covered by a three-year warranty. Intel reserves its five-year SSD warranties for the 320 and 520 Series, whose high-endurance NAND is cherry-picked off the standard 25-nm production line. I suspect it will take Intel some time to bin enough higher-grade, 20-nm NAND to fuel upgrades to those other models.
Our performance results will illustrate how the 335 Series compares up to those other Intel SSDs. Expect the 320 Series to be much slower due to its 3Gbps Serial ATA interface. That drive’s Intel flash controller can trace its roots back to the original X25-M, so the design is a little long in the tooth. The 520 Series, however, has a 6Gbps interface and higher performance specifications than the 335 Series. The two are based on the same SandForce controller silicon, though.
A mostly refined package
Although Intel got its start in the SSD business using proprietary controller technology, third-party tech can be found in most of its SSDs today. The 330, 520, and now 335 Series all use the same SandForce SF-2281 flash controller. This chip was first unveiled in February of 2011, and it seems to have left behind the firmware-based BSOD issues that plagued its early life. Intel has only been selling SSDs based on the SF-2281 since February of this year, when the 520 Series made its debut.
If you’ve been following the SSD scene, you should be familiar with the SF-2281. The chip pairs a 6Gbps SATA interface with eight individual NAND channels. Unlike most SSD controllers, it doesn’t require separate cache memory. The chip’s internal buffers are large enough to take care of business without resorting to an external DRAM cache.
The defining characteristic of SandForce’s controller technology is DuraClass, a black box of technologies that includes a funky write-compression scheme dubbed DuraWrite. SandForce has kept the inner workings of DuraWrite close to its vest, but we know that it uses lossless, on-the-fly compression to reduce the flash footprint of incoming writes from the host. By writing less data to the flash, DuraWrite aims to increase the longevity of the NAND while also improving performance.
Flash memory, of course, can withstand only a limited number of write-erase cycles. The less data is written, the fewer of those cycles are consumed, and the longer the flash should last. Writing less data should also take less time, resulting in higher performance. DuraWrite’s potential benefits are bound by the compressibility of the data being written, though. Data that’s already been compressed or is highly random in nature has less to gain from SandForce’s bit-scrambling mojo than, say, a repeating pattern of bits and bytes.
DuraClass also includes a hardware encryption engine, but the Intel 335 Series’ product documentation makes no mention of encryption support. Encryption support is nowhere to be found in the supporting materials for the 330 Series, either, but it is a prominent feature of the 520 Series. Incidentally, Intel had a hand in uncovering a flaw in the SandForce controller’s 256-bit AES encryption. As a result, the 520 Series’ encryption support was downgraded from 256 to 128 bits.
RAISE is another component of SandForce’s DuraClass special sauce. This RAID-like redundancy scheme is designed to protect against physical flash failures; typically, it can keep the drive’s data intact after the demise of an entire flash die. RAISE is supported on higher-capacity models in the old 330 Series, and it appears to persist in the 335 Series.
The 335 Series actually lacks lower-capacity models entirely. In fact, the 240GB model is the only member of the line. Intel expects this to be the most popular capacity, and given current prices, it’s hard to argue with that sentiment. 240-256GB drives tend to offer the lowest cost per gigabyte right now. Intel plans to “evaluate demand” before committing to adding other capacities to the 335 Series. In the meantime, the 330 Series will continue to be sold.
As you can see in the picture above, our 335 Series sample looks a little bit rough. The top of the drive’s case is unblemished, but the bottom looks like it just got kicked out of Chris Brown’s Lamborghini. This isn’t a one-off offense, either; we’ve seem similarly beaten-up panels on Intel’s 320 and 520 Series SSDs. Intel says the cases meet its fit and finish requirements, which are apparently pretty lax on the finish front.
The case conforms to the 9.5-mm version of the 2.5″ form factor used by typical SSDs. Most notebooks can accommodate 9.5-mm drives, but it’s worth noting that the 320 and 520 Series use slimmer cases that can slip into 7-mm bays. Each of those drives comes with a screwed-on spacer that beefs up the thickness to 9.5 mm. Oddly, that spacer moves inside the case for the Intel 335 Series.
Popping open the case also reveals the circuit board, which is loaded with 16 NAND packages. There are eight packages per side, and each one has dual 8GB dies. Add ’em up, and the drive has 256GB of flash memory onboard. Some of the NAND is dedicated to spare area and RAISE, dropping the 335 Series’ advertised capacity to 240GB.
Our drive arrived in a retail kit that includes a 3.5″ mounting bracket, SATA data and power cables, and a handful of screws. Intel provides free cloning software for folks looking to migrate an existing OS install to the SSD. It also offers an excellent SSD Toolbox application that’s worth downloading regardless of whether you’re cloning a current drive or starting from scratch.
Among other things, this utility can be used to secure-erase the drive and to update its firmware. It can also be configured to TRIM unused flash pages on a schedule, if you don’t trust the drive and operating system to clean up after themselves. I particularly like the app’s estimated life display, which is based on a SMART attribute that tracks flash wear. The SSD Toolbox can be used to monitor that and other SMART attributes, including ones that keep tabs on the total volume of reads and writes. According to the app, our test suite has hammered the drive with 3.5TB of reads and 2.5TB of writes.
Our testing methods
We’ve freshened our suite of SSD results with a couple of additions from OCZ. The Vertex 4 256GB has been added to the mix, replacing the 512GB drive we tested initially. We’ve also added the Agility 4 256GB, a cheaper version of the Vertex that uses the same Marvell controller and Indilinx firmware but slower NAND. Both drives are running OCZ’s latest firmware.
Crucial updated the firmware for its m4 SSD not long ago, and we’re running the latest version on that drive. As far as we’re aware, though, none of the other drives we’ve tested have newer firmware revisions that promise substantially better performance.
We’ve included a Western Digital Caviar Black mechanical desktop drive for reference, which gives us more than enough fodder for overstuffed graphs. Our test methods and systems haven’t changed in probably a little too long, so the scores on the following pages can be compared to those in any of our storage reviews dating back to last September. We’re already contemplating tests for a new suite, but the week after Windows 8’s official launch wasn’t a good time to bust those out.
If you’re familiar with our test 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. Our collection of SSDs includes representatives based on the most popular SSD configurations on the market right now. We’re working on getting Samsung’s new 840 Series SSDs in-house for testing, so stay tuned.
|Corsair Force Series 3 240GB||6Gbps||NA||SandForce SF-2281||25-nm Micron async MLC|
|Corsair Force Series GT 240GB||6GBps||NA||SandForce SF-2281||25-nm Intel sync MLC|
|Corsair Neutron 240GB||6GBps||256MB||LAMD LM87800||25-nm Micron sync MLC|
|Corsair Neutron GTX 240GB||6GBps||256MB||LAMD LM87800||26-nm Toshiba Toggle DDR|
|Crucial m4 256GB||6Gbps||256MB||Marvell 88SS9174||25-nm Micron sync MLC|
|Intel 320 Series 300GB||3Gbps||64MB||Intel PC29AS21BA0||25-nm Intel MLC|
|Intel 335 Series 240GB||6Gbps||NA||SandForce SF-2281||20-nm Intel sync MLC|
|Intel 520 Series 240GB||6Gbps||NA||SandForce SF-2281||25-nm Intel sync MLC|
|OCZ Agility 4 256GB||6Gbps||512MB||Indilinx Everest 2||25-nm Micron async MLC|
|OCZ Vertex 4 256GB||6Gbps||1GB||Indilinx Everest 2||25-nm Intel sync MLC|
|Samsung 830 Series 256GB||6Gbps||256MB||Samsung S4LJ204X01||2x-nm Samsung Toggle DDR|
|WD Caviar Black 1TB||6Gbps||64MB||NA||NA|
We used the following system configuration for testing:
|Processor||Intel Core i5-2500K 3.3GHz|
|Motherboard||Asus P8P67 Deluxe|
|Platform hub||Intel P67 Express|
|Platform drivers||INF update 220.127.116.110
|Memory size||8GB (2 DIMMs)|
|Memory type||Corsair Vengeance DDR3 SDRAM at 1333MHz|
|Audio||Realtek ALC892 with 2.62 drivers|
|Graphics||Asus EAH6670/DIS/1GD5 1GB with Catalyst 11.7 drivers|
|Hard drives||Corsair Force 3 Series 240GB with 1.3.2 firmware
Corsair Force Series GT 240GB with 1.3.2 firmware
Crucial m4 256GB with 010G firmware
Intel 320 Series 300GB with 4PC10362 firmware
WD Caviar Black 1TB with 05.01D05 firmware
OCZ Agility 4 256GB with 1.5.2 firmware
Samsung 830 Series 256GB with CXM03B1Q firmware
Intel 520 Series 240GB with 400i firmware
OCZ Vertex 4 256GB with 1.5 firmware
Corsair Neutron 240GB with M206 firmware
Corsair Neutron GTX 240GB with M206 firmware
Intel 335 Series 240GB with 335s 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:
- Intel IOMeter 1.1.0 RC1
- HD Tune 4.61
- TR DriveBench 1.0
- TR DriveBench 2.0
- TR FileBench 0.2
- Qt SDK 2010.05
- MiniGW GCC 4.4.0
- Duke Nukem Forever
- Portal 2
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 data created by the full test also 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 Intel 335 Series and our mechanical hard drive compare to different SSDs.
To make the graphs easier to interpret, we’ve greyed out the mechanical drive. The SSD results have been colored by drive maker, with the 335 Series set apart from Intel’s other, er, series in a darker shade of blue.
The Intel 335 Series gets off to a good start, just edging out the 520 Series in HD Tune’s sequential read speed test. That performance isn’t good enough to put the 335 Series on the podium, but it does place the drive ahead of all the other SandForce-based SSDs we’ve tested.
Admittedly, the line graphs for the read speed test provide little drama. It’s worth noting that the SSDs maintain their transfer rates across the full extent of the drives, unlike the HDD, but that’s about it. Things get more interesting when we look at write performance:
SSDs based on SandForce controllers have long exhibited a series of regularly-spaced performance spikes in this test. The Intel 335 Series fits this pattern exactly. Interestingly, Corsair’s Neutron SSDs behave similarly but have much lower write speeds between their peaks. The Neutrons are based on a new controller from Link_A_Media Devices, otherwise known as LAMD.
If you look at the averages, the Intel 335 Series pulls up just short of the 520 Series and the Corsair Force Series GT, drives that combine the same SandForce controller with 25-nm synchronous NAND. There’s quite a gap between those three SSDs and our two leaders, the OCZ Vertex 4 and the Samsung 830 Series, which turn in write speeds about 100MB/s higher than anything else.
HD Tune runs on unpartitioned drives, a setup that isn’t always ideal for SSDs. For another perspective, we ran CrystalDiskMark’s sequential transfer rate tests, which call for partitioned drives. We used the app’s default settings: a 1GB transfer size with randomized data.
The Intel 335 Series pulls up just shy of 500MB/s in the read speed test, barely behind the 520 Series but a good 40MB/s off the pace set by the Samsung SSD. The field is a little more spread out in the write speed test. There, CrystalDiskMark’s use of randomized data is less than ideal for the SandForce-based drives. The 335 Series is the fastest among them, but that’s only good for sixth place overall.
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 couple 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 drive.
The line graph is there to illustrate the massive gap in random access times between solid-state and mechanical storage. You’re looking at a difference of more than an order of magnitude for the smaller transfer sizes. The SSDs start to slow down appreciably when we hit the largest transfer size, though.
With 1MB random reads, the Intel 335 Series’ access time is just 0.01 milliseconds lower than the leader of the bunch. In the 4KB test, the 335 Series is just 0.001 milliseconds out of first place. Intel’s latest SSD pretty much ties the other SandForce-based drives in these tests.
Switching to random writes doesn’t change the picture appreciably. Our traditional hard drive is still woefully uncompetitive, as our line graph plainly illustrates. Near-instantaneous access times are what make SSDs feel so much faster than mechanical drives.
If we concentrate on the SSDs in the 4KB and 1MB tests, the Intel 335 Series looks very competitive. It has the quickest access time in the 1MB test and is within striking distance of the lead in the 4KB one. Again, the 335 Series’ performance matches what we see from other the SandForce-based SSDs.
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|
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. We haven’t found a substantial difference in the performance of mechanical drives between these two states. Let’s start with the fresh-state results.
Like the other SandForce-based SSDs, the Intel 335 Series is particularly adept at copying the smaller, easily compressed files in our TR and Mozilla sets. It boasts the fastest copy speeds in those tests, although it does have to share the limelight with other drives based on the same controller.
Clearly, SandForce’s DuraWrite voodoo isn’t as effective when dealing with the heavily compressed files in the movie, MP3, and RAW sets. In those tests, the 335 Series is a middle-of-the-pack performer and notably slower than a number of its peers. The other SandForce SSDs don’t fare much better.
The overall dynamic doesn’t change dramatically when we move to our used-state file copy tests. All of the SandForce-based drives, including the Intel 335 Series, fare better when copying the Mozilla and TR sets than they do with the movie, MP3, and RAW sets.
SandForce-based SSDs tend to be less aggressive than the competition when it comes to reclaiming unused flash pages, causing used-state copy speeds to be slower than when the drives are fresh from a secure erase. The 335 Series is no exception, with used-state copy speeds down as much as 17% compared to what the drive can do in a fresh state. That drop-off is comparable to the slowdowns exhibited by the other SandForce drives, although the numbers are a little different from one file set to the next. Apart from the SandForce drives, none of the other SSDs suffer consistently slower used-state copy speeds.
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.
SandForce-based SSDs take the top three spots in DriveBench, and the Intel 335 Series is right up there with the leaders. It’s barely slower than the 520 Series and the Force Series GT but more comfortably ahead of Corsair’s Neutron GTX. Wanna bet on whether the SandForce drives are clustered together in the individual test results?
Yeah, that’s easy money. Although the Intel 335 Series slips out of the top three when our multitasking workload includes copying files, it’s never far from the 520 Series and the Force Series GT. I suspect the SandForce controller’s sensitivity to compressed data is what holds back its performance in the file copy component of DriveBench 1.0.
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 Intel 335 Series comes ever so close to taking the top spot in DriveBench 2.0. Its mean service time is just 0.01 milliseconds off the pace set by the Samsung 830 Series and the Corsair Neutron GTX. Surprise, surprise, the other synchronous SandForce configs turn in similar performances. Let’s slice and dice the results to see if we can find any intrigue.
Well, here’s some. The SandForce controller, and by extension the Intel 335 Series, is particularly adept at serving read requests. It’s not as competitive with writes, causing the 335 Series to fall into fifth place. The Samsung 830 Series, Corsair’s Neutrons, and the OCZ Vertex 4 all have quicker mean write service times than the SandForce posse in DriveBench 2.0.
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 can give us a sense of how much service times vary from the mean.
The read results show the top six drives very closely matched. That’s good for the Intel 335 Series, which sits comfortably in the middle of that lead group. The 335 Series exhibits less variability in its write service times than the other SandForce drives, but it’s not quite as consistent as the Neutrons or the Samsung 830 Series.
Another way to characterize service times is to sort them. We’re going to close out our DriveBench analysis with a final set of graphs showing the percentage of service times longer than 100 ms. These extremely long service times have the potential to cause the sort of hitching that a user might notice.
The Intel 335 Series barely has any 100+ ms service times, regardless of whether we consider reads or writes. Not all the SSDs are so lucky. The Agility 4, Vertex 4, and m4 all have notably higher percentages of extremely long service times for both reads and writes. The actual percentages are still under 0.3% for those SSDs, though.
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.
Well, that’s a surprise. The Intel 335 Series crunches more IOps than the 520 Series in three of four tests, particularly under heavier loads. The 520 Series only comes out ahead in the web server test, which is made up exclusively of read requests.
That said, none of the SandForce-based drives contends for top honors here. Our use of randomized data likely handicaps the performance of those drives in the file server, database, and workstation tests, which mix read and write requests. However, the read-only web server test shouldn’t be affected by DuraWrite at all. There, the SandForce SSDs have lower IOps rates than a number of their rivals, including the Samsung 830 Series, Corsair’s Neutrons, and the OCZ Vertex 4. The Neutrons and the Vertex 4 have higher transaction rates than the Intel 335 Series regardless of the workload or the number of concurrent I/O requests.
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 7 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.
Our load time results make one thing pretty clear: any of these SSDs has substantially faster load times than a mechanical hard drive. The gaps between the individual SSDs are relatively small, with the Intel 335 Series sitting comfortably in the top half of the pack.
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.
We have a new low-power leader, at least at idle. Intel’s latest draws just half a watt when sitting at the Windows desktop, which is a little bit less than the Force Series GT and the Crucial m4.
Under a strenuous IOMeter load, the Intel 335 Series’ power consumption increases sixfold, putting the drive in the middle of the pack. The leaders in that test, Intel’s own 320 Series and the Crucial m4, consume about half as much power or less.
The value perspective
Welcome to another one of our famous value analyses, which adds capacity and pricing to the performance data we’ve explored over the preceding pages. We used Newegg prices to even the playing field, and we didn’t take mail-in rebates into account when performing our calculations. Since the Intel 335 Series isn’t selling online as I write this, we’ve had to use the drive’s $184 suggested retail price.
First, we’ll look at the all-important cost per gigabyte, which we’ve obtained using the amount of storage capacity accessible to users in Windows.
Traditionally, Intel SSDs have had higher prices than the competition. That doesn’t appear to be the case with the 335 Series, whose MSRP yields a cost per gigabyte of just 77 cents. Based on this metric alone, the only better deal is the Samsung 830 Series, a drive that appears to be heavily discounted to make room for the new 840 family.
Of course, our lone mechanical hard drive costs less per gig than any of the SSDs. It’s not in the same league in terms of performance, which we’ll now take into account.
Our remaining value calculation uses a single performance score that we’ve derived by comparing how each drive stacks up against a common baseline provided by the Momentus 5400.4, a 2.5″ notebook drive with a painfully slow 5,400-RPM spindle speed. This index uses a subset of our performance data described on this page of our last SSD round-up.
The 335 Series is fast enough for second place overall, wedged between the Samsung 830 Series and Intel’s own 520 Series. The top five drives are clustered within 19 percentage points of each other, and the next two are no more than 20 points behind. However, the gaps get substantially wider after that.
Now for the real magic. We can plot this overall score on one axis and each drive’s cost per gigabyte on the other to create a scatter plot of performance per dollar per gigabyte. The best place on the plot is the upper-left corner, which combines high performance with a low price.
We’ve had to really shorten the drive names because so many of the SSDs are clustered in the same performance band. Differences in pricing help to spread things out a little, and that’s what really separates the top contenders.
With the lowest cost per gigabyte and the highest performance score overall, Samsung’s 830 Series is closest to the upper-left corner on our plot. The Intel 335 Series occupies the second-most-attractive spot, though. It costs less than all the other SSDs short of the 830 Series, yet it boasts one of the highest performance ratings of the bunch.
Intel is arguably better at mass-producing semiconductors than anyone else in the business. That prowess has served its microprocessor division well, and it’s definitely paying dividends on SSD front. Of the ever-growing number of companies churning out solid-state drives, Intel is one of very few with its own NAND production capacity. That capacity is shared with Micron through IM Flash Technologies, a joint venture responsible for the flash chips in most of the SSDs to pass through our labs over the past few years, regardless of the name on the case.
You see, in addition to producing chips for its own SSDs, Intel sells flash to its competitors. Intel makes money on both fronts, and its SSDs have first dibs on NAND rolling off the production line. Right now, the latest and greatest is an 8GB NAND die built using 20-nm fabrication technology. Thanks to its smaller die area, the new NAND should be cheaper to produce than the old 25-nm stuff. And, thanks to a new high-k/metal gate cell structure, it should be just as fast and reliable.
We’ve had our 335 Series drive for less than a week, so we can’t speak to the drive’s reliability. However, we can tell you that it’s every bit as fast as comparable offerings based on 25-nm NAND. The 335 Series is still subject to the quirks of its SandForce controller, specifically lower write performance with compressed data, but it’s wicked-fast overall. Of the SSDs we’ve tested, only the Samsung 830 Series scores higher in our overall performance index, and then only by a slim margin.
Intel SSDs have always had competitive performance, but they’ve typically been saddled with higher price tags than their peers. Even today, the 320 and 520 Series command a hefty premium over drives that offer equivalent or faster performance. The 335 Series is different, though. With a $184 suggested retail price, the 240GB drive costs less than most of its direct rivals. You don’t get a five-year warranty like with the 320 and 520 Series, but for most folks, three-year coverage will be more than sufficient.
Right now, the only thing that spoils the debut of the Intel 335 Series 240GB is the fact that Samsung’s 830 Series 256GB costs a little bit less and offers slightly more storage. The Samsung drive is on its way out, though, and the most desirable variant is already out of stock at Newegg (although still available at Amazon). The 335 Series looks like a better bet going forward, providing street prices come close Intel’s target. At $184, the Intel 335 Series 240GB definitely hits the sweet spot—and is good enough for our coveted Editor’s Choice award.