HD Tach will test the sequential read, random access and interface burst speeds of your attached storage device (hard drive, flash drive, removable drive, etc). All drive technologies such as SCSI, IDE/ATA, 1394, USB, SATA and RAID are supported. Test results from HD Tach can be used to confirm manufacturer specs, analyze your system for proper performance, and compare your performance with others. HD Tach is very easy to use, quick, and presents data in easy to read graphs, including the ability to compare two storage devices on screen at the same time for easy analysis.
The Caviar SE16 750GB is the only drive tested here with the 300MB/s transfer system in place, so it has a burst speed well beyond that of the other two WD drives. The average transfer speeds show the read performance to be on par with that of the Raptor drive though the write performance falls behind BOTH the Raptor and 400GB Caviar drive. Random access time and CPU utilization are decent but not amazing and the Raptor definitely leads the pack with 8.1 ms thanks to its higher rotational speed.