HD Tach is a low level hardware benchmark for random access read/write storage devices such as hard drives, removable drives (ZIP/JAZZ), flash devices, and RAID arrays. HD Tach uses custom device drivers and other low level Windows interfaces to bypass as many layers of software as possible and get as close to the physical performance of the device possible.
Benchmark Results: The Western Digital VelociRaptor was the clear winner on HD Tach 3.0.4! The burst speed of 251.4 MB/s made the 132.9 MB/s seen on the 150GB Raptor look like a joke. The random access time was 1ms lower on the VelociRaptor and the CPU usage was the same. The Raptor is obviously SATA 1.5 and is the reason that the performance tops off just under 150 MB/s for the burst speed. This just goes to show how badly WD need an enthusiast SATA 3.0 drive! It should be noted that for this test that both were secondary drives on the same system. The average read speed was found to be 36.6% faster on the VelociRaptor!