Our testing methods
Before dipping into pages of benchmark graphs, let's set the stage with a quick look at other the players we've assembled for comparative reference. We've called up a wide range of competitors, including a selection of desktop hard drives, traditional notebook drives, Seagate's Momentus XT hybrid, and a stack of pure solid-state goodness. Below is a chart highlighting some of the key attributes of the contenders we've lined up to face our quartet of 7,200-RPM notebook drives.
|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 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 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 performance results for the 3.5" drives aren't entirely relevant to our focus on notebook models, they do provide a handy point of reference for desktop users. Despite much higher prices, SSDs share the same 2.5" form factor as mechanical notebook drives. Like it or not, they're direct competition.
On the SSD front, we've collected all the other relevant players, including drives based on Indilinx, Intel, JMicron, Marvell, SandForce, and Toshiba controllers. Although it might not seem like a fair fight, we've also thrown in results for a striped RAID 0 array built using a pair of Intel's X25-V SSDs. The X25-V only runs a little more 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 126.96.36.1994 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 SSD testing methods in greater detail. Before testing the drives, each was returned to a factory-fresh state with a secure erase, which empties all the flash pages on a drive. Next, we fired up HD Tune and ran full-disk read and write speed tests. The TRIM command requires that drives have a file system in place, but since HD Tune requires an unpartitioned drive, TRIM won't be a factor in those tests.
After HD Tune, we partitioned the drives and kicked 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 deleted that file before moving onto our file copy tests, after which we restored an image to each drive for some application testing. Incidentally, creating and deleting IOMeter's full-disk file and the associated partition didn'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. Testing drives in a used state may put the TRIM-less Plextor SSD at a disadvantage, but I'm not inclined to indulge the drive just because it's using a dated controller chip.
To make our massive collection of results a little easier to interpret, we've colored our bar charts by drive type. This color coding separates the SSDs from the mechanical drives and highlights the four 7,200-RPM notebook models that are the focus of this round-up.
Most of our tests run on drives connected as secondary storage, so we were able to use the Caviar Green's full 3TB with our test system's default configuration, which uses the Microsoft AHCI drivers built into Windows 7. However, as we explained in our review, the Green has issues operating at full capacity when running as a system drive, at least with current drivers and non-EFI BIOSes. Rather than moving the Green to an auxiliary storage controller that sees the Caviar's full capacity as a system drive, we'd rather stick with the motherboard's P55 chipset and live with slightly less capacity. Switching storage controllers would make the results less comparable, and the impact of running the Green at a little less than full capacity should be negligible considering that our boot and system partition only amounts to 100GB, most of which is unused.
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.
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.