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 not an issue. We see a sequential average read speed of 120 MB/sec. The higher the better of course.

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. Here obviously .. the smaller number  means better.

SiSoft Sandra HD test

Let's do a very synthetic test with Sandra, just to see if we can match the results we've seen in ATTO. Sandra fires of a series of READ/WRITE tests at the drive and than averages it. What SANDRA also does (important for a HDD) is to test at several positions of the HD. See, at the inner part of a platter the performance is slower.

We first look at Random access time, the lower the better. Since the SSD does not have a head to mechanically move around, the OCZ Core SSD had an access time of well below <1ms where the traditional HDDs range between 8 to 14ms.

The Drive Index test is what I mentioned. The higher the better. The Samsung Spinpoint (5400 RPM) averages at 44 MB/sec. The Maxtor 200GB (7400 RPM) at 47 MB/sec. The WD Raptor is real fast at 70 MB/sec and then the SSD again shows brilliant performance up-to 116 MB/sec speeds.

Subjective tests

To take the test a little bit further, away from synthetic testing, I decided to make a clean install of Windows Vista on the SSD drive. For two full days I have been working on that system, playing some games .. work a little on it, just basic normal PC usage. And I just have to admit .. I love it. Really fast access times versus good speed and no noise. What's not to like ?

Also what was noticeable is system bootup-time, Windows Vista boots up in 21 seconds, which is roughly a minute on my primary test system with a WD Raptor. In all fairness, the SSD Vista installation was fresh and clean.

For you as a gamer I did a subjective test as well. Call of Duty 4. Starting up the game and load times feel just so much faster.

• On the Raptor is takes 22 seconds to startup the Ghilly suit level
• On the OCZ SSD is takes 12 seconds to startup the Ghilly suit level

So compared to a raptor we can say that the SSD from OCZ results on a 40%-50% faster load time. Again, that's compared to a fast & expensive WD Raptor.

Impressive to say at the least.