Our testing methods
Before burying you under a deluge of benchmark graphs, let's take a quick look at the mix of rivals we've put together to face the Scorpio Black 750GB, and the methods we use to test storage devices here at TR. We include these details to help you better understand and replicate our results, but if you're already familiar with our approach to storage testing, feel free to skip ahead to the benchmarks. We won't be offended.
The Scorpio Black's most direct competition comes from other 7,200-RPM notebook drives. We've tested the latest ones from Hitachi, Samsung, and Seagate, plus a few entries from Western Digital's own stable. Seagate's Momentus XT mechanical/SSD hybrid is included in the mix, as is a stack of solid-state drives that share the same 2.5" form factor as the Scorpio. For comparative reference, we've also included results from a collection of 3.5" mechanical drives. Below is a chart outlining several key characteristics that can affect the performance of the contenders we've lined up.
|Flash controller||Interface speed||Spindle speed||Cache size||Platter capacity||Total capacity|
|Corsair Force F100||SandForce SF-1200||3Gbps||NA||NA||NA||100GB|
|Corsair Force F120||SandForce SF-1200||3Gbps||NA||NA||NA||120GB|
|Corsair Nova V128||Indilinx Barefoot ECO||3Gbps||NA||64MB||NA||128GB|
|Crucial RealSSD C300||Marvell 88SS9174||6Gbps||NA||256MB||NA||256GB|
|Hitachi Deskstar 7K1000.C||NA||3Gbps||7,200 RPM||32MB||500GB||1TB|
|Hitachi Travelstar 7K500||NA||3Gbps||7,200 RPM||16MB||250GB||500GB|
|Intel X25-M G2||Intel PC29AS21BA0||3Gbps||NA||32MB||NA||160GB|
|Intel X25-V||Intel PC29AS21BA0||3Gbps||NA||32MB||NA||40GB|
|Kingston SSDNow V+||Toshiba T6UG1XBG||3Gbps||NA||128MB||NA||128GB|
|OCZ Agility 2||SandForce SF-1200||3Gbps||NA||NA||NA||100GB|
|OCZ Vertex 2||SandForce SF-1200||3Gbps||NA||NA||NA||100GB|
|Plextor PX-128M1S||Marvell 88SSE8014||3Gbps||NA||128MB||NA||128GB|
|Samsung 470 Series||Samsung S3C29MAX01||3Gbps||NA||256MB||NA||256GB|
|Samsung Spinpoint F3||NA||3Gbps||7,200 RPM||32MB||500GB||1TB|
|Samsung Spinpoint MP4||NA||3Gbps||7,200 RPM||16MB||320GB||640GB|
|Seagate Barracuda 7200.12||NA||3Gbps||7,200 RPM||32MB||500GB||1TB|
|Seagate Barracuda LP||NA||3Gbps||5,900 RPM||32MB||500GB||2TB|
|Seagate Barracuda XT||NA||6Gbps||7,200 RPM||64MB||500GB||2TB|
|Seagate Momentus 7200.4||NA||3Gbps||7,200 RPM||16MB||250GB||500GB|
|Seagate Momentus 750GB||NA||3Gbps||7,200 RPM||16MB||375GB||750GB|
|Seagate Momentus XT||NA||3Gbps||7,200 RPM||32MB||250GB||500GB|
|WD Caviar Black 1TB||NA||6Gbps||7,200 RPM||64MB||500GB||1TB|
|WD Caviar Black 2TB||NA||3Gbps||7,200 RPM||64MB||500GB||2TB|
|WD Caviar Green 2TB||NA||3Gbps||5,400 RPM||32MB||500GB||2TB|
|WD Caviar Green 3TB||NA||3Gbps||5,400 RPM||64MB||750GB||3TB|
|WD Scorpio Black 320GB||NA||3Gbps||NA||16MB||160GB||320GB|
|WD Scorpio Black 500GB||NA||3Gbps||7,200 RPM||16MB||250GB||500GB|
|WD Scorpio Black 750GB||NA||3Gbps||7,200 RPM||16MB||375GB||750GB|
|WD Scorpio Blue||NA||3Gbps||5,400 RPM||8MB||375GB||750GB|
|WD SiliconEdge Blue||JMicron JMF612||3Gbps||NA||64MB||NA||256GB|
|WD VelociRaptor VR150M||NA||3Gbps||10,000 RPM||16MB||150GB||300GB|
|WD VelociRaptor VR200M||NA||3Gbps||10,000 RPM||32MB||200GB||600GB|
Although it might not seem like a fair fight, we've thrown in results for a striped RAID 0 array built using a pair of Intel's X25-V SSDs. The X25-V costs less than $100 online, making multi-drive RAID arrays affordable enough to be tempting for desktop users. Our X25-V array was configured using Intel's P55 storage controller, the default 128KB stripe size, and the company's latest 188.8.131.524 Rapid Storage Technology drivers.
The block-rewrite penalty inherent to SSDs and the TRIM command designed to offset it both complicate our testing somewhat, so I should explain our methods in greater detail. Before testing SSDs, each is returned to a factory-fresh state with a secure erase, which empties all the flash pages on the drive. Next, we fire up HD Tune and run full-disk read and write speed tests. The TRIM command requires that drives have a file system in place, but since HD Tune runs on an unpartitioned drive, TRIM won't be a factor in those tests.
After HD Tune, we partition the drives and kick off our usual IOMeter scripts, which are now aligned to 4KB sectors. When running on a partitioned drive, IOMeter first fills it with a single file, firmly putting SSDs into a used state in which all of their flash pages have been occupied. We delete that file before moving onto our file copy tests, after which we restore an image to each drive for some application testing. Incidentally, creating and deleting IOMeter's full-disk file and the associated partition doesn't affect HD Tune transfer rates or access times.
Our methods should ensure that each SSD is tested on an even, used-state playing field. However, differences in how eagerly an SSD elects to erase trimmed flash pages could affect performance in our tests and in the real world.
To make our massive collection of results a little easier to interpret, we've marked the SSDs and 3.5" mechanical drives in different shades of grey. The 2.5" notebook drives are color-coded by manufacturer, at least in the bar charts, and there's a multi-colored rainbow to cover the line graphs. You should be able to spot the Scorpio Black easily; it's colored in black throughout the graphs.
With few exceptions, all tests were run at least three times, and we reported the median of the scores produced. We used the following system configuration for testing:
You can read more about the hardware that makes up our twin storage test systems on this page of our VelociRaptor VR200M review. Thanks to Gigabyte for providing the twins' motherboards and graphics cards, OCZ for the memory and PSUs, Western Digital for the system drives, and Thermaltake for SpinQ heatsinks that keep the Core i5s cool.
We used the following versions of our test applications:
- WorldBench 6
- Intel IOMeter 2006.07.27
- Xbit Labs File Copy Test 0.3
- HD Tune 4.01
- Visual Studio 2008 with 03-23-2010 Firefox source
- Call of Duty: Modern Warfare 2
- Crysis Warhead
The test systems' Windows desktop was set at 1280x1024 in 32-bit color at a 75Hz screen refresh rate. Vertical refresh sync (vsync) was disabled for all tests.
Some further notes on our methods:
- Noise levels were measured with a TES-52 Digital Sound Level meter 1" from the side of the drives at idle and under an HD Tune seek load. Drives were run with their PCBs facing up next to our open-air test bench.
- For our power consumption tests, we measured the voltage drop across a 0.1-ohm resistor placed in line with the 5V and 12V lines connected to each drive. We were able to calculate the power draw from each voltage rail and add them together for the total power draw of the drive. The drives were tested under a load consisting of 256 outstanding I/O requests using the workstation access pattern. Power consumption was also probed while idling at the Windows desktop one minute after halting our IOMeter load.
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.