SSDs have cornered the market for high-performance system drives, relegating their mechanical counterparts to secondary storage. Traditional hard drives are simply too slow to keep up with the flash-based alternatives that have taken the PC industry by storm.
That said, mechanical drives still have an undisputed claim to the mass-storage crown. Flash memory’s blistering performance comes at a price—literally. Even after years of falling flash prices, solid-state storage still costs a lot more per gigabyte than traditional hard drives. Mechanical drives are also available in much higher capacities.
Seagate’s Desktop HDD.15 is a perfect example. This latest addition to the mechanical field squeezes four terabytes into a single 3.5″ case. It’s also eminently affordable. You’ll pay just $190 for the thing, which works out to a nickel per gig. The per-gigabyte cost of even budget SSDs is an order of magnitude higher.
The Desktop HDD.15 is the most affordable 4TB hard drive on the market, which isn’t too surprising. While the competition spins its platters at 7,200 RPM, the HDD.15 has a slower 5,900-RPM spindle speed.
Slower rotational speeds are nothing new on the desktop; low-power “green” drives have employed them for years. We typically see slower spindles used to bring up new platter technologies, and that’s exactly what’s happening here. The Desktop HDD.15 is the first four-disc implementation of Seagate’s terabyte platters.
The platters have an extremely high areal density of 625 Gb/in². Their individual tracks measure 75 nm wide, or about a thousand times narrower than the average human hair. Accessing data on such a small scale is no easy feat, especially given the speeds involved. At 5,900 RPM, the outer edge of the platter is moving at the equivalent of 61 miles an hour. Increasing the rotational speed to 7,200 RPM boosts the outer-edge velocity to 75 MPH. No wonder drive makers usually start new configurations at a slower speed.
Of course, even low-speed hard drives need to be incredibly precise. Because there’s so little room for error, environmental vibration can interfere with normal operation, causing the drive head to drift off-track or dangerously close to the surface of the platter. The Desktop HDD.15 features AccuTrac servo tech to maintain read and write performance in what Seagate describes as “high-touch” environments. An all-in-one system pumping music through built-in speakers is provided as one example of such an environment. The product guide also suggests the HDD.15 is ideal for desktop RAID and NAS applications, both of which entail ambient vibration due to the close proximity of other drives.
OptiCache describes the dual-core storage processor and associated technologies that blanket most members of Seagate’s Desktop HDD family. The ARM-based chip is fabbed on a 40-nm process, and it’s infused with improved caching algorithms that work in conjunction with 64MB of DRAM memory. This is a straight-up mechanical drive, so there’s no NAND involved.
|Spindle speed||5,900 RPM|
|Average data rate||146MB/s|
|Max sustained data rate||180MB/s|
|Idle acoustics||2.3 bels|
|Operating acoustics||2.8 bels|
|Typical operating power||7.5W|
|Warranty length||Two years|
The Desktop HDD.15’s slower spindle speed produces lower average and maximum sustained data rates than those of Seagate’s 7,200-RPM offerings. Those drives stack as many as three of the same terabyte platters, and they’re rated for an average speed of 156MB/s and sustained peak of 210MB/s.
The performance of mechanical drives usually hinges on the combination of spindle speed and areal density. However, other factors clearly influence the Desktop HDD.15. The drive spins its platters 18% slower than Seagate’s 7,200-RPM desktop drives, yet its average data rate drops only 6%. The HDD.15’s maximum data rate is 14% lower, which is closer to what we’d expect given the difference in spindle speed.
We’ll examine actual performance in a moment. First, I have an axe to grind. The Desktop HDD.15’s warranty coverage runs out after two years. That doesn’t mean the drive will spontaneously combust when the term expires. However, the relatively short coverage doesn’t inspire confidence in a product that will store four terabytes of precious data. It wasn’t too long ago that all of Seagate’s internal hard drives had five-year warranties.
Ok, so it was about 4.5 years ago—pretty much an eternity in the PC industry. If you want a 4TB drive with a five-year warranty today, you have to spring for the WD Black, which rings in at $300. Speaking of the Black, let’s move on to our comparative performance tests.
Lining up the competition
Before diving into our results, we should introduce a new competitor. We wanted a low-power drive to square off against the Desktop HDD.15, so we scored a WD Red 3TB for comparison. Like the HDD.15, the Red has one terabyte per platter and a relatively slow spindle speed. Its capacity tops out at 3TB, though.
The Red 3TB is basically a RAID-optimized version of the WD Green, which is the original low-power desktop drive. Both have the same 145MB/s transfer rate specification. You can find the Red 3TB selling online for $150, which is $10 more than the equivalent Green model.
In addition to the Red, we have a stack of other mechanical hard drives. The collection includes WD’s Black 4TB along with a couple of older, lower-capacity versions of the Black from back when the family had Caviar in its name. 3TB drives from Hitachi and Seagate are on the menu, as well.
You’ll want to pay particular attention to how the Desktop HDD.15 fares against the Barracuda 3TB. The latter uses the same platters as its 4TB sibling but spins them at a much higher 7,200 RPM.
Deskstar 7K3000 3TB
|6Gbps||64MB||7,200 RPM||411 Gb/in²|
|6Gbps||64MB||7,200 RPM||625 Gb/in²|
Desktop HDD.15 4TB
|6Gbps||64MB||5,900 RPM||625 Gb/in²|
Caviar Black 1TB
|6Gbps||64MB||7,200 RPM||400 Gb/in²|
Caviar Black 2TB
|6Gbps||64MB||7,200 RPM||400 Gb/in²|
VelociRaptor VR200M 600GB
A pair of 10k-RPM VelociRaptors is also in the mix, although they’re not direct rivals to the Desktop HDD.15. The Raptors are, however, two of the fastest mechanical drives around.
While it’s hard to rationalize how a 4TB mechanical hard drive really competes with SSDs that cost at least ten times more per gigabyte and tend to be capped at one eighth the total capacity, the comparison has to be made. Here’s the stack of solid-state drives that will be squaring off against the mechanical field.
|Crucial m4 256GB||256MB||Marvell 88SS9174||25nm Micron sync MLC|
|Intel 335 Series 240GB||NA||SandForce SF-2281||20nm Intel sync MLC|
|OCZ Agility 4 256GB||512MB||Indilinx Everest 2||25nm Micron async MLC|
|OCZ Vector 256GB||512MB||Indilinx Barefoot 3||25nm Intel sync MLC|
|Samsung 840 Series 250GB||512MB||Samsung MDX||21nm Samsung Toggle TLC|
|Samsung 840 Pro 256GB||512MB||Samsung MDX||21nm Samsung Toggle MLC|
These six drives nicely cover some of the more popular controller and NAND combinations for modern SSDs. We have representatives from the high end of the spectrum, the more affordable side, and multiple points in between. All the drives are in the 240-256GB range, and you’ll want to keep those limited capacities in mind. In desktop systems, SSDs are best thought of as complementary to mechanical storage rather than as replacements for it.
If you’re a TR regular already familiar with our storage test system and methods, feel free to skip ahead to the performance results. Apart from minor tweaks to the table below, the rest of this page is copied lazily from previous reviews.
Our test methods
We used the following system configuration for testing:
Core i5-2500K 3.3GHz
Asus P8P67 Deluxe
|Platform hub||Intel P67
|Platform drivers||INF update
|Memory size||8GB (2
Corsair Vengeance DDR3 SDRAM at 1333MHz
ALC892 with 2.62 drivers
Asus EAH6670/DIS/1GD5 1GB with Catalyst 11.7 drivers
|Hard drives||Crucial m4
256GB with 010G firmware
Intel 335 Series 240GB with 335s firmware
OCZ Agility 4 256GB with 1.5.2 firmware
OCZ Vector 256GB with 10200000 firmware
Samsung 840 Series 250GB with DXT07B0Q firmware
Samsung 840 Pro Series 256GB with DXM04B0Q firmware
Hitachi Deskstar 7K3000 3TB with MKA0A580 firmware
Seagate Barracuda 3TB with CC47 firmware
Seagate Desktop HDD.15 4TB with B660 firmware
WD Caviar Black 1TB with 05.01D05 firmware
WD Caviar Black 2TB with 01.00101 firmware
WD Red 3TB with 80.00A80 firmware
WD VelociRaptor VR200M 600GB with 04.05G04 firmware
WD VelociRaptor 1TB with 04.06A00 firmware
WD Black 4TB with 01.01L01 firmware
Corsair Professional Series Gold AX650W
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.
With SSDs increasingly serving our high-performance storage needs, the acoustic footprint of hard drives has arguably become a more important differentiating factor—especially for PC enthusiasts who have built themselves near-silent systems. We’re a little OCD here at TR, so we’ve constructed a Box ‘o Silence to test the noise emitted by mechanical hard drives. This 18″ x 20″ anechoic chamber is lined with acoustic foam, and we suspend hard drives inside it, exactly 4″ away from the tip of our TES-52 digital sound level meter. You can read more about the setup here.
To ensure the lowest possible ambient noise levels, we swapped the test system’s graphics card for a passively cooled Gigabyte model and unplugged one of the Frio CPU cooler’s dual fans. Noise levels were measured after one minute of idling at the Windows desktop and during an HD Tune seek test.
We’ve color-coded the results by manufacturer to make the graphs easier to read, marking the Desktop HDD.15 4TB with a darker shade of green than the other Seagate drive. Because they have no moving parts and are essentially silent, the SSDs are missing from the noise results. When they do appear in the graphs, the corresponding bars are greyed out to set apart what is really a different class of PC storage.
The Desktop HDD.15 is a little quieter than its 7,200-RPM sibling at idle, but the two make about the same amount of noise when seeking. Seagate’s acoustic specifications put the two drives on relatively equal footing, and our results agree. Any acoustic advantage imparted by the HDD.15’s slower spindle speed is likely nixed by the addition of the fourth platter. We’ve found four-platter drives to be generally louder than their three-platter counterparts.
That said, the Desktop HDD.15 is still a very quiet drive. It registers a couple decibels below the WD Black 4TB at idle and nearly seven decibels lower while seeking. The HDD.15’s seek chatter sounds muffled, especially when compared to that of the Black. Clearly, though, the WD Red is our low-noise leader. The thing barely makes a whisper regardless of whether it’s idling or seeking.
We should note that, even when idling at the Windows desktop, the Desktop HDD.15 vibrates enough to make the suspension cords in our test chamber oscillate with a slight hum. When this happens, the drive starts chirping audibly—perhaps an artifact of AccuSync adjusting for the vibration. Putting a paperback book on top of the drive adds enough weight to tension the cords, dampen the vibration, and eliminate the chirping. Apart from cutting out vibration-induced noise, the book’s presence doesn’t appear to change the HDD.15’s decibel output. We tested the WD Black 4TB with and without the book and found no difference in the readings on our meter.
Power consumption was tested 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.
Thanks in part to its lower spindle speed, the Desktop HDD.15 consumes relatively little power. Under load, it draws less than half of the wattage pulled by the Black 4TB. The WD Red does consume fewer watts than the HDD.15, but it’s a terabyte behind on the storage front.
HD Tune — Transfer rates
HD Tune lets us look at transfer rates across the extent of the drive, and we’ve plotted the full profiles for the mechanical drives in the line graphs below. The SSDs are fast enough to throw off the scale, so we’ve left them out. You can click the buttons below each of the line graphs to see how the Desktop HDD.15 4TB compares to different classes of competitors.
Despite its spindle speed disadvantage, the Desktop HDD.15 tops the average sequential read speed of the Black 4TB by nearly 10MB/s. The HDD.15’s higher-density platters help to offset the damage done by its slower rotational speed. Those same platters yield an extra 18MB/s when spinning at 7,200 RPM in the Barracuda 3TB.
You have to go further down the standings to find the Red 3TB, which manages only 116MB/s in this test. I suppose that’s not too bad. Hitachi’s 7,200-RPM Deskstar 7K3000 has the same average read rate.
While our fastest mechanical drives come close to equaling the read speed of the slowest SSD, all the other solid-state offerings are well ahead. No wonder SSDs are preferred for performance-sensitive applications.
Switching to HD Tune’s write speed test changes little. The SSDs are still way ahead of the mechanical drives, and the Desktop HDD.15’s relative position in the field is unaltered. The line graphs reveal no hiccups in the HDD.15’s transfer rate profiles.
This next test measures the speed of short “burst” transfers that target the DRAM caches on traditional hard drives.
Although Seagate touts the Desktop HDD.15’s 64MB cache, the drive’s burst performance is relatively weak. The Barracuda 3TB boasts much higher scores in these tests, as do most of the mechanical drives, including the Black 4TB.
SSDs use their DRAM caches differently than hard drives, and some don’t have them at all. That’s probably why the results for the solid-state and mechanical drives are so mixed in these tests.
HD Tune — Random access times
Our next set of HD Tune tests probe random access times with various transfer sizes. We’ll start with a line graph showing all the results for the mechanical drives before moving onto bar charts that cover a couple of key transfer sizes.
Slower spindle speeds translate to slower access times. The Desktop HDD.15’s read access times aren’t egregiously high, since the Seagate drive fares better than the WD Red, but they’re a long way from matching the performance of the Black 4TB. Even the 7,200-RPM Barracuda can’t keep up with the Black.
The SSDs, on the other hand, blow the mechanical drives out of the water. Their advantage narrows in the 1MB test, but it’s still no contest.
Well, this is weird. We’ve seen several hard drives turn in odd scores in HD tune’s 512-byte random write test. However, this is the first time a drive has also posted substantially higher access times in the 4KB and 64KB tests. Only in the 1MB test is the HDD.15 competitive with its peers.
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.
The SSDs were tested in a simulated used state that should be representative of their long-term performance. We didn’t simulate a used state with the mechanical drives or hybrids, which tend to offer consistent performance regardless of whether we’ve run our used-state torture test.
The Desktop HDD.15’s copy speeds look pretty decent with the larger files in the movie, MP3, and RAW sets. In those tests, the HDD.15 is within striking distance of the WD Black 4TB. However, the gap between the two widens in the TR and Mozilla tests, which involve much larger numbers of smaller files.
Interestingly, the WD Red copies those smaller files faster than the HDD.15. The Red has slower copy speeds with larger files, though.
Once again, the SSDs dominate the standings. Their advantage isn’t as pronounced when copying smaller files, but it’s positively huge when working with larger ones.
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.
Surprisingly, the Desktop HDD.15 matches the DriveBench performance of the 7,200-RPM Barracuda. The Black 4TB turns in a much higher score, and even the Red has a slight edge over the Seagate drives. Let’s look at the individual scores that comprise our overall average.
There’s really no silver lining for the Desktop HDD.15; it’s slow across the board. The Red pushes more IOps in every test but the transcoding one, where it ties with the HDD.15 at the back of the pack. The Black 4TB enjoys a comfortable lead over the Seagate drives throughout.
Admittedly, disk-intensive multitasking is a sort of worst-case scenario for mechanical storage. SSDs handle the load with ease, as our performance results illustrate.
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.
Neither of the Seagate drives performs well in DriveBench 2.0. They both sit at the back of the pack, with the Desktop HDD.15 slightly behind the Barracuda. The ‘cuda turns in the same mean service time as the WD Red, which is much slower than the Black 4TB.
The SSDs are way out in front again. Surprise!
Let’s slice and dice the data with a few more metrics. We’ll start by splitting mean service times between read and write requests.
The Desktop HDD.15 has problems with both reads and writes. With the latter, its mean service time is actually a bit quicker than that of the Barracuda. Both Seagate drives trail the WD Red, and they’re well behind the Black 4TB.
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.
Interesting. There’s little difference in the variability of service times between the Desktop HDD.15 and Barracuda. The duo’s standard deviation for reads isn’t too far off the marks set by the Black 4TB and the Red 3TB. However, the Seagate drives exhibit a lot more variance in write performance than their mechanical peers.
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. You can click the buttons below the graphs to see how the Desktop HDD.15 compares to different classes of mechanical and solid-state drives.
Well, there’s your problem right there. And there. And there. Sorry, I’m typing out loud as I click the buttons. Across all the plots, the Desktop HDD.15 has fewer service times under just about every threshold. The exceptions are few and far between, and the bulk of them occur below the 0.1-millisecond mark, which is too quick to really feel.
You may, however, notice extremely long service times that spike above 100 milliseconds. That threshold is over on the far right of the plot, where the drives bunch together and differences are difficult to see. Let’s zoom in on the results and compare the percentages of service times above 100 ms.
While the values are low overall, the Desktop HDD.15’s are the highest for both reads and writes. Keep in mind that the results pertain to nearly two weeks of I/O activity. Even a small percentage adds up to a substantial number of long access times.
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.
There’s too much data to easily show on a single graph for each access pattern, so we’ve once again split the results by drive class. You can compare the Desktop HDD.15’s performance to that of the competition by clicking the buttons below each graph. Note that the scale is different for the Raptor results.
We’ve also banished the SSDs from this set of results. Their transaction rates demand a much higher scale, making it impossible to discern what’s going on with the mechanical drives. You can see how the SSDs compare on this page of our Samsung 840 Pro Series review.
In the read-only web server test, the Desktop HDD.15 scrapes the bottom of the barrel along with the WD Red. Both have lower I/O rates than the 7,200-RPM drives, which are led by a pack of WD Black models. There’s actually a substantial difference between the Blacks and the second tier of 7,200-RPM mechanical drives.
Our IOMeter tests are sensitive to random access times, so slower spindle speeds can be a big handicap. The Raptors illustrate that fact perfectly—just as long as you notice the change in scale on the vertical axis.
The rest of our IOMeter tests mix read and write requests, but the results don’t change appreciably. The Desktop HDD.15 is still outclassed by its 7,200-RPM rivals, and the Raptors are another level above that.
In a fairer fight, the HDD.15 stays one step ahead of the WD Red. The Seagate drive has a slight edge almost throughout, but it stumbles with lighter loads in the file server test.
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.
The Desktop HDD.15’s boot time is 1.4 seconds slower than the WD Red’s, 2.2 seconds behind the Barracuda’s, and 2.5 seconds shy of the Black 4TB’s. And the SSDs? They’ll get you into Windows in less than half the time.
Level load times
Again, the Desktop HDD.15 brings up the rear. It’s about as far from the mechanical competition as in our boot test—a few seconds at worst.
The delta between solid-state and mechanical storage is much starker. It’s difficult to tell the difference between the various SSDs, though. Pretty much any halfway-decent SSD will deliver much quicker load times than the best hard drives.
The value perspective
Welcome to our famous value analysis, which adds capacity and pricing to the performance data we’ve explored over the preceding pages. We used Newegg to price all of the drives, and we didn’t take mail-in rebates into account when performing our calculations.
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.
Although the Barracuda 3TB is our cost-per-gig champion, the Desktop HDD.15 looks pretty sweet. $180 for 4TB works out to $0.05 per gigabyte. At $300 for the same capacity, the Black 4TB is more expensive than the two-cent difference above suggests.
The SSDs are an order of magnitude more expensive on this value scale. Their actual price tags are in the same range as the high-capacity mechanical drives, though. Our collection of SSDs runs $180-270 online.
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.
If you’ve been paying attention, this result shouldn’t be unexpected. The Desktop HDD.15 has the lowest overall score of the bunch. Its closest rival is the WD Red, which is also hamstrung by a slow spindle speed. Neither of those two drives comes close to the Black 4TB, which scores higher than all the mechanical models short of the 10k-RPM VelociRaptors.
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.
With the lowest performance and per-gigabyte cost, the Desktop HDD.15 occupies an interesting spot on the plot. It’s very affordable, especially when one considers the total capacity. For the same money, though, the Barracuda and Red are notably faster.
The Black 4TB is a lot faster overall. It also costs close to 50% more, which seems entirely fair given the performance gap. Of course, if you really want something faster, you want an SSD.
The solid-state drives are so much faster—and so much pricier—that they jack up the scale of our plot. There’s no room for labels for the mechanical drives, although it really doesn’t matter. Even without them, the plot nicely illustrates both sides of the expansive gulf between the two prevailing classes of PC storage.
The Desktop HDD.15 is an impressive hard drive. It packs four terabytes for only $190—by far the lowest asking price of any 4TB SATA offering. Seagate reaches that capacity with only four platters, which is a first in the industry. Competing solutions need five platters to match the HDD.15.
Of course, Seagate had to make a trade-off to cram four terabyte platters into a single drive. The company dialed back the spindle speed to 5,900 RPM, putting the HDD.15 at a distinct disadvantage versus typical desktop drives. The 7,200-RPM WD Black 4TB delivers much higher all-around performance. So does Seagate’s own Barracuda 3TB, which spins three of the HDD.15’s platters at the same speed as the Black.
While the results on the preceding pages clearly illustrate the performance gaps between the Desktop HDD.15 and other mechanical hard drives, it seems a little silly to focus on them given the big grey elephant in the, er, graphs. If storage performance is a concern, you should probably be looking at an SSD. These days, hard drives are best left to secondary storage.
In that role, the Desktop HDD.15 is a solid value. If all you’re doing is storing media files, data archives, and Linux ISOs, the HDD.15’s sluggish performance probably won’t be an issue. The drive’s low idle noise level and muted seek chatter will complement a silent SSD nicely, as well. The Desktop HDD.15 isn’t as quiet as WD’s low-power Red 3TB, but it makes less noise than any of the 7,200-RPM drives we’ve tested, including the Black 4TB.
In the end, the Desktop HDD.15 feels like the mini van of PC storage; it provides maximum space with minimum joy. Thankfully, it doesn’t have to be your daily driver. You can park one in the garage next to a small, sporty SSD.