SSDs get most of the attention, but mechanical hard drives are still a big part of the PC storage industry. Their capacity expands with each new generation, driving down the cost of a gigabyte to just pennies—a full order of magnitude lower than even the most affordable solid-state drives. Thanks to higher bit densities, each new family of mechanical models still tends to offer better performance than the last. Drive makers seem to be paying more attention to acoustics, too, resulting in ever-quieter noise levels.
There is one category in which mechanical hard drives are getting worse, though. Just a few years back, three- and five-year warranties were common. Then, in 2011, Seagate and Western Digital both cut the coverage for most of their internal drives. Two years became the new norm, and the timing left a sour aftertaste. Earlier that year, we’d witnessed major consolidation with the industry as Western Digital acquired Hitachi’s hard drive business and Seagate picked up Samsung’s HDD division. We’d also watched drive prices skyrocket as massive flooding in Thailand took out multiple production facilities.
These days, five-year hard drive warranties are largely limited to expensive enterprise-class gear. On the desktop, the last remaining hold-outs are Western Digital’s VelociRaptor and Black families. We’ve already covered the former, which occupies unique middle ground between traditional hard drives and SSDs. Now, it’s time to turn our attention to the Black.
The top of the line is the Black 4TB, and you can probably guess how much storage it has. The capacity is spread across five 800GB platters, which is a bit of a departure from the norm for WD. The company has traditionally used four-platter designs to hit capacity milestones. It’s typically reached those new high-water marks first with low-power 5,400-RPM drives, as well. The Black is indeed WD’s first 4TB consumer drive, but it has a much faster 7,200-RPM spindle speed. (Although Western Digital sells a 4TB version of its external My Book series, that product actually uses a Hitachi hard drive rather than one of WD’s own design.)
Western Digital hasn’t revealed the areal density of the Black’s platters. However, we do know the bits are accessed with a dual-stage actuator. The first stage involves the main arm, which gets the drive head in the general vicinity of the desired track. At the tip of the main arm sits a smaller, secondary arm powered by a piezoelectric actuator. This second stage provides more precise fine-tuning. The secondary arm has enough range to cover multiple tracks, allowing “short seeks” to be served without any movement of the main actuator.
As it turns out, the Black isn’t the only 4TB drive with five platters and two actuator stages. Hitachi’s Deskstar 7K4000 shares those characteristics. The Black 4TB isn’t the product of cross-pollination between the Deskstar division and its new parent company, though. Western Digital tells us there’s no sharing between itself and Hitachi Global Storage. The two firms are operated as separate companies, although they are at least working together in some capacity on WD’s external My Book products.
Like other members of the Black line, the 4TB model has a dual-processor controller chip linked to a 6Gbps Serial ATA interface and 64MB of DRAM cache. A dynamic caching algorithm adjusts how the onboard memory is allocated based on the distribution of read and write traffic from the host system. The cache’s 64 megabyte footprint is minuscule compared to the multi-gigabyte flash arrays employed by hybrid storage configurations, so don’t get your hopes up. Mechanical drives have had 64MB DRAM caches for years.
Western Digital’s higher-capacity desktop models use a StableTrac motor shaft that’s anchored at both ends to cut down on vibration. This more secure mounting mechanism is can be found on the 4TB, 3TB, and 2TB Black variants but not on the 1TB and 500GB units. Those lower-capacity models also have lower performance ratings than the 4TB drive, whose sustained transfer rate peaks at 154MB/s. Here are the official specifications:
|Spindle speed||7,200 RPM|
|Max sustained transfer rate||154MB/s|
|Idle acoustics||29 dBA|
|Seek acoustics||34 dBA|
|Warranty length||Five years|
No surprises there. You might be surprised by the $300 street price, though. That works out to about seven cents per gigabyte, which is pretty affordable for a flagship offering with few peers.
There simply aren’t many 4TB consumer drives on the market right now. In fact, the WD Black is one of only two with a 7,200-RPM spindle speed. The other is the Deskstar 7K4000, which is no longer listed as a bare drive on Hitachi’s site. It appears the WD subsidiary is now focused on selling that Deskstar as part of a retail kit. We’ve tried for months to get Hitachi to send us one for testing, but despite being told initially that a drive would be shipped out, we’ve yet to receive the 7K4000.
Seagate has a 4TB drive of its own: the Desktop HDD.15, whose 5,900-RPM spindle speed puts it in a different class of storage products. That model is on its way to the Benchmarking Sweatshop, and we should have a review for you soon.
But I digress. It’s time to get back to the Black and see how this mechanical monster performs.
Lining up the competition
To put the Black 4TB’s performance into perspective, we’ve assembled a stack of other mechanical hard drives. The collection includes older, lower-capacity versions of the Black from back when the family had Caviar in its name. Also on the menu: 3TB drives from Seagate and Hitachi, both of which feature 7,200-RPM spindle speeds.
|Interface||Cache||Spindle speed||Areal density|
|Hitachi Deskstar 7K3000 3TB||6Gbps||64MB||7,200 RPM||411 Gb/in²|
|Seagate Barracuda 3TB||6Gbps||64MB||7,200 RPM||625 Gb/in²|
|Seagate Momentus XT 750GB||6Gbps||32MB||7,200 RPM||541 Gb/in²|
|WD Caviar Black 1TB||6Gbps||64MB||7,200 RPM||400 Gb/in²|
|WD Caviar Black 2TB||6Gbps||64MB||7,200 RPM||400 Gb/in²|
|WD Black 4TB||6Gbps||64MB||7,200 RPM||NA|
|WD Scorpio Black 750GB||3Gbps||16MB||7,200 RPM||520 Gb/in²|
|WD VelociRaptor VR200M 600GB||6Gbps||32MB||10,000 RPM||NA|
|WD VelociRaptor 1TB||6Gbps||64MB||10,000 RPM||NA|
A pair of 10k-RPM VelociRaptors is also in the mix, although they’re not really direct rivals to the Black 4TB. They are, however, two of the fastest mechanical drives around, and they both have five-year warranties. The Scorpio Black and Momentus XT give us a taste of what some of the best drives from the notebook scene have to offer, and the latter has a dash of flash-based hybrid caching for good measure.
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 a replacement for it.
If you’re a TR 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:
|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||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 Momentus XT 750GB with SM12 firmware
WD Caviar Black 1TB with 05.01D05 firmware
WD Caviar Black 2TB with 01.00101 firmware
WD Scorpio Black 750GB with 01.01A01 firmware
WD VelociRaptor VR200M 600GB with 04.05G04 firmware
WD VelociRaptor 1TB with 04.06A00 firmware
WD Black 4TB with 01.01L01 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.
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’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 Black 4TB with a brighter shade of blue than the other WD drives. 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 Black 4TB is nearly the quietest 3.5″ desktop drive of the bunch, humming just a fraction of a decibel louder than the Barracuda 3TB. That’s a particularly impressive achievement considering the ‘cuda has only three platters. Drives with fewer platters are typically quieter, a point nicely illustrated by the louder drone of the five-platter Deskstar 7K3000 3TB.
While those Hitachi and Seagate drives only get about a decibel louder when seeking, the Black 4TB’s noise output jumps substantially. And audibly. The pitch of the chatter isn’t too shrill, which is a relief.
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 Black 4TB’s power draw is the highest of the bunch under load and nearly the highest at idle. For the same reason they tend to be louder—more weight for the motor to spin—drives with higher platter counts tend to consume more power. Note that the five-platter Deskstar is also relatively power-hungry. Don’t worry too much about differences of just a few watts, though. Those add up to a drop in the bucket on the average desktop user’s utility bill.
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 Black 4TB compares to different classes of competitors.
The Barracuda 3TB has much higher sequential read rates than the Black 4TB. Really, it should. With 200GB more per platter, the ‘cuda has a higher areal density. The bits are packed more tightly, so more of them pass under the drive head with each revolution of the platter.
The bar chart highlights the huge gulf in performance between the mechanical drives and all but the slowest SSD in the bunch. The best solid-state solutions are more than three times faster than the Black 4TB here.
The SSDs aren’t quite so much faster in HD Tune’s write speed test, but they still outclass the mechanical drives by a longshot. Again, the Black 4TB trails well behind the Barracuda 3TB. The Black boasts higher write speeds than the Deskstar, though.
This next test measures the speed of short “burst” transfers that target the DRAM caches on traditional hard drives.
Although the Black 4TB’s read burst speed is only good enough for the middle of the pack, its performance in the write test registers third place overall, ahead of even the mighty VelociRaptor. In both cases, the Black 4TB has a faster burst rate than the high-capacity drives from Hitachi and Seagate.
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.
There are a couple of interesting things going on in the line graph. First, notice how the Momentus XT is the only participant with really low access times through the 64KB transfer size. That’s the result of the drive’s NAND cache, which speculatively loads data to serve read requests.
The Black 4TB’s random read access times are quite low for a 7,200-RPM drive. With 4KB transfers, the Black is more than three milliseconds quicker than the Barracuda and Deskstar. It doesn’t have as much of an edge over the ‘cuda in the 1MB test, where even the SSDs start to slow down. The SSDs are still in another class entirely, though.
The random write results don’t change the narrative much. The Momentus XT’s hybrid cache can’t service write requests, so it doesn’t have SSD-like access times for the smaller transfer sizes. There are also some out-of-character results for a handful of drives in the 512-byte test, which could be due to quirks associated with implementing larger 4KB sectors.
As in the random read test, the Black 4TB is quicker overall than its Deskstar competition. However, the 3TB Seagate drive sneaks ahead by less than a millisecond in the 1MB test.
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.
Well, well. The Black 4TB may not match the Barracuda’s copy speed with the large files in our movie, MP3, and RAW sets, but it offers higher throughput with the smaller files in the Mozilla and TR sets. Interestingly, the Deskstar has similar performance characteristics, nearly matching the Black in each test.
The delta between the solid-state and mechanical drives is much tighter with smaller files. In the Mozilla and TR tests, the slowest SSDs are just a few MB/s ahead of the Black 4TB, and the fastest options are about twice as fast. Move to larger files, and even the most plodding SSD doubles the Black’s copy speed. The leaders copy our movie, MP3, and RAW files nearly four times faster than the 4TB WD drive.
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.
Our multitasking tests favor random access times over raw sequential throughput, and that seems to suit the Black 4TB. The drive is second only to the VelociRaptors in the mechanical field and has a healthy lead over the Deskstar. The Barracuda is way behind, while the SSDs predictably score much higher. Let’s see what the individual test results tell us.
The Black 4TB’s performance is consistently solid throughout, with the Barracuda only drawing close in the transcoding test. The Deskstar maintains a similar distance no matter what the workload.
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.
Our longer trace-based test shows the Black 4TB in an attractive light. The drive is more responsive overall than any other 7,200-RPM drive except the Momentus XT, whose mechanical platters are aided by an 8GB flash sidekick. Nothing can touch the SSDs at the front of the field.
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.
Notice how the Momentus XT’s advantage over the Black 4TB only exists for reads, which can be served out of its NAND cache. This iteration of Seagate’s hybrid tech doesn’t do write caching.
The Black 4TB doesn’t appear to favor read or write requests. It has low service times with both and offers much snappier write performance than the other high-capacity offerings. The Deskstar’s mean read service time is nearly as fast, though.
While the SSDs are mostly faster than the mechanical drives when serving DriveBench 2.0’s read requests, the Black 4TB actually has a quicker mean write service time than the Crucial m4. It’s not that far behind the Samsung 840 Series, either.
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 Black has quite a bit less variance in its write service times than the other 7,200-RPM contenders. However, its read variance is only middle of the pack.
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 Black 4TB Series compares to different classes of mechanical and solid-state drives.
What’s important to see here is how the percentage curve for the Black is higher than the ones for every other mechanical drive short of the VelociRaptor 1TB. This is true across just about the entire range of threshold points, although things start to pile up at 100 milliseconds. A final set of DriveBench graphs gives us a closer look at those extremely long access times.
Only small fractions of the Black 4TB’s service times exceed 100 milliseconds, and the percentage with writes is extremely low compared to the 3TB drives from Hitachi and Seagate. The results are closer when we consider only read requests.
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 Black 4TB’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.
The web server access pattern is made up exclusively of read requests, so it’s a good place to start. Here, the Black 4TB sticks close to the other WD desktop drives. They all have higher transaction rates than the Barracuda and Deskstar models at each and every step of our scaling load.
That same template persists through our remaining three access patterns, all of which mix read and write requests. The Black 4TB scores higher than the Barracuda and Deskstar drives regardless of the access pattern or the number of concurrent I/O requests.
Transaction rates in our IOMeter workloads are dictated largely by random I/O performance. That’s why the VelociRaptors score so much higher than the Black 4TB.
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.
None of the high-capacity drives load the OS particularly quickly, and the Black 4TB is no exception. Less than a second separates it from the Barracuda and Deskstar.
Level load times
The Black 4TB has similarly slim advantages over the Barracuda and Deskstar in our load time tests. Here and in our boot duration test, the SSDs have a distinct edge over the mechanical drives. Even the Momentus XT hybrid struggles to keep up with the strictly solid-state club.
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.
The Barracuda 3TB is easily our value champion on this scale. Seven cents per gig isn’t too bad for a high-capacity flagship like the Black 4TB, though. That drive costs only a penny more per gig than the Deskstar 7K3000 3TB, and it’s much more affordable than any of the SSDs.
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.
To no one’s surprise, the SSDs sew up the top spots. The Black 4TB must be content to sit at the head of the pack of 7,200-RPM drives, where it enjoys healthy leads over the Barracuda and Deskstar units. Among mechanical drives, only the 10k-RPM VelociRaptors score higher than the Black overall.
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.
I tried to squeeze in labels for the mechanical drives, but those data points are far too close together to fit the text elegantly. This abbreviated first plot does, however, provide a nice illustration of what are ultimately two very different classes of PC storage. SSDs offer very high performance at a very high cost, while mechanical drives are much slower—and cheaper per gig.
With the SSDs handled, let’s zoom in on the mechanical results to get a better sense of where the Black 4TB sits versus its more direct competition.
WD’s top-of-the-line Black delivers a nice step up in performance over the high-capacity Barracuda and Deskstar drives without costing too much more per gigabyte. The VelociRaptors don’t look nearly as appealing. They may boast higher overall scores than the Black, but they cost several times more per gig. If you’re going to give up capacity for performance, you’re probably better off going all the way and getting an SSD.
In a sense, the Western Digital Black 4TB has no equals. There are only two consumer-grade drives on the market with the same capacity and 7,200-RPM spindle speed, and this is the only one with five-year warranty coverage. You’d expect to pay a premium to be part of such an exclusive club, but the Black isn’t too pricey. It’s selling for $300 online, which works out to just seven cents per gigabyte.
The asking price is similar to the going rate for Hitachi’s Deskstar 7K4000, which has the same capacity and spindle speed but only a three-year warranty. Seagate’s freshly released Desktop HDD.15 also boasts 4TB of storage, but its platters rotate at just 5,900 RPM, and the warranty runs out after a measly two years. No wonder the HDD.15’s $190 street price is so low.
Bargain hunters looking to pair solid-state system drives with mechanical mass storage for media libraries and other miscellaneous files may be better served by cheaper offerings like the HDD.15. The fact is that performance is less important when all you’re doing is streaming music and movies. Low-power drives also tend to be quieter—especially when seeking, which produces an audible chatter on the Black 4TB. Those reasons have prompted us to recommend pairing SSDs with low-power mechanical drives in several of our system guides.
Drives with spindle speeds around 5,400-RPM are invariably slower than 7,200-RPM models, though. Their random access times tend to be particularly sluggish, and that’s an area where the Black 4TB excels even versus its 7,200-RPM rivals. If you need your hard drive to do more than just house FLAC songs and Blu-ray rips, the Black 4TB starts to make a lot of sense. Its strong all-around performance and massive capacity are good fits for content creation and video editing professionals who need more storage than SSDs can provide at a reasonable cost.
I’d even be inclined to recommend the Black for high-end desktop rigs on the strength of its low idle noise levels and five-year warranty coverage. Even if you’re running a solid-state system drive, some games will surely spill into mechanical storage; you don’t want to wait too long for them to load. I’m not sure I’d want my growing collection of RAW image files residing on a slow hard drive, either. The Black 4TB is an appealing sidekick in the right setting.