Western Digital hatched its latest Raptor back in April, revealing a unique departure from more traditional designs. This leaner, meaner VelociRaptor VR150 is actually a 2.5" drive sitting inside a heatsink that slides nicely into standard 3.5" bays. But don't think you can take this most recent Raptor lightly just because it's gone on a diet. Despite a smaller form factor, the VelociRaptor still offers 300GB of capacity—twice that of its 3.5" forebear. The VR150 is also the first Raptor with a 300MB/s Serial ATA interface, and its trademark 10K-RPM spindle speed hasn't skipped a beat.

Like its predecessors in their prime, the VelociRaptor proved to be the all-around fastest SATA hard drive on the market—and a surprisingly quiet and power-efficient one, at that. However, the drive we used in our initial look at the VR150 was an engineering sample with pre-production firmware. Final, production drives have now made their way onto the market, and we've managed to score a retail sample that should be representative of the drives you can buy today.

Naturally, we've run this tuned-up VelociRaptor through the wringer to see if it can live up to the Editor's Choice distinction we awarded the VR150 after our first encounter. Read on to see whether finished firmware reels in the VelociRaptor's propensity to outrun the competition or if Western Digital has managed to wring even more performance from its radical Raptor redesign.

Test notes
We'll be comparing the performance of the VelociRaptor with that of a slew of competitors, including some of the latest and greatest Serial ATA drives from Hitachi, Samsung, Seagate, and Western Digital. These drives differ when it comes to external transfer rates, spindle speeds, cache sizes, platter densities, and capacity, all of which can have an impact on performance. Keep in mind the following differences as we move through our benchmarks:

We should note that our WD1500ADFD has a slightly newer firmware revision than the Raptor X sample we've had since February 2006. The drives still share identical internals, but firmware optimizations could give our newer Raptor an edge over the X in some tests.

Performance data from such a daunting collection of drives can make our graphs a little hard to read, so we've color-coded our bar graphs based on each drive's manufacturer. We've also used some fancy fade effects to make the VelociRaptor stand out a little from the rest of the pack. You'll find color-coding in our line graphs, too, but pay close attention, because the colors don't match our bar charts.

Naturally, we've included VelociRaptor engineering sample results from our initial review of the drive. Pay special attention to how these VelociRaptor ES scores compare with those of our final VR150.

Our testing methods
All tests were run three times, and their results were averaged, using the following test system.

Thanks to the folks at Newegg for hooking us up with the DiamondMax 11 we used for testing. Also, thanks to NCIX for getting us the Deskstar 7K1000 and Spinpoint F1.

Our test system was powered by OCZ PowerStream power supply units. The PowerStream was one of our Editor's Choice winners in our last PSU round-up.

We used the following versions of our test applications:

• WorldBench 5.0
• Intel IOMeter v2004.07.30
• Xbit Labs File Copy Test v1.0 beta 13
• TCD Labs HD Tach v3.01
• Far Cry v1.3
• DOOM 3
• Intel iPEAK Storage Performance Toolkit 3.0

The test systems' Windows desktop was set at 1280x1024 in 32-bit color at an 85Hz screen refresh rate. Vertical refresh sync (vsync) was disabled for all tests.

All 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.