RAID 0 Performance with 2 drives, advice needed.

Need some advice from the pros and experienced users.


Have decided to try out RAID, got a pair of Seagate Barracudas 7200.11 320GB ( ST3320613AS, 7200RPM ).

Mobo is P5B Deluxe. Plugged em in, altered BIOS settings, CTRL+I after POST and created 2 disk arrays, one with 550GB (for games + downloads), other is 47GB (for OS). Then copied Intel Matrix Floppy Driver onto USB stick, inserted the DVD-ROM with OS (Windows 7 beta 7048) and started to install. Upon installation clicked "Advanced Install" and when the dialog for partition appeared, clicked "Drive Options (Advanced)" and proceeded to install the Intel 7.0.0.1020 driver from the USB flash drive. In a few minutes it was complete. I benchmarked with hdtune, hdtach and these are the results.





As you can see, the blue is the bigger 550GB, the red is 47GB. So here are a few questions.

Is it normal that the raid arrays size affects the read and burst performance of RAID, on 2 identical drives?
Since the 550GB array (can we call that partition?) has increased Random Access time, yet higher Average Read. Could you please explain please? Would 2 equal sized arrays have equal performance then? OR perhaps there was a mistake during installation, or Windows 7 is buggy, or some other factor.

Ahhhh... interesting, thank you for such an educational reply! Will change the order. Do the speeds seem about correct for a RAID 0? Looking at the bench results on TomsH., they seem to have higher average reads, perhaps they used one raid array partition using the whole platter, and on that basis the average was higher.