HD Tach is a physical performance hard drive test that uses a special kernel mode VXD to get maximum accuracy by bypassing the file system.

The HD Tach sequential read test is a little bit different from other benchmarks. Most benchmarks create a file on the hard drive and test within that file. The problem is that modern hard drives use a zone bit recording technique that allows different read speeds depending on where the data is located. Data on the outside of the drive is much faster than data recorded on the inside. Obviously for SSD this is not an issue.

HDTach shows that SLC SSDs are faster, included in this test is a Silicon power 32 GB SLD drive as well.

Yet when we compare the MLC OCZ Core and Patriot Warp drives again, the Warp SSD takes a lead and positions itself on a sturdy second place. OCZ Core however was their first revision SSD, and they now have numerous faster version available.

In addition to sequential read, HD Tach tests the drive's random access time. Random access is the true measure of seek speed. Many drives advertise sub 10 millisecond seek speeds, but seek speeds are misleading. Also again, without a head that needs moving around, the SSDs are just soooo fast as they have no mechanical moving parts. Here obviously .. the smaller number is better, 0,2 ms (!).

Also we can show you the write performance, with just one little hiccup showing, the drive manages to write at an average of roughly 90 MB/sec incredible consistent.