QUOTE(Reuben @ Feb 13 2008, 06:46 PM)
Btw if you are using Vista you need not reinstall your Vista. (sorry didn't have the time to read back if you were using XP or Vista).
Vista works fine with AHCI, and you will not run into problems with a new install. However, if you change this setting underneath an installed Vista, it will likely blue-screen on you. The trick is to edit the registry setting here:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
Edit the Start key and change its value to 0. Then shut down, change the BIOS to AHCI, and reboot. All going well, Vista will detect the change, install new drivers, ask you to reboot once more, and it's done.
Please also see my other post regarding AHCI vs IDE before deciding to make the jump just to enable NCQ.
http://forum.lowyat.net/index.php?showtopi...post&p=15630042You may find that you may not actually need to bother.
Yeah, I did read your post in that thread which started by me regarding AHCI vs IDE. Finally, someone with real experience stood up and help me out with it

.
Actually personally, I might not bother switching into AHCI mode till my system crashed twice (yesterday and just now). The first time it happened, I was rebooting my system and then suddenly the system indicating a missing system file at location "C://Windows/Config/" or similar... I couldn't remember as I didn't jot it down. Then I forced RESET and the 4th or 5th time I managed to load Windows. I run a ScanDisk check on D: and it took too long till I do another RESET *I just couldn't cancel it

*. The system then went to the same state and I did a Windows Recovery Installation using WinXP BootDisk. The system then runs normal.
I left my rig run over night as I'm downloading a huge file which about 3GB++. I was at work and suddenly my sister SMSed me telling me that the system suddenly BSOD and restarted. She told me that she read something about "Disk Read Error". Well, I switched ON my rig now and it runs normally. I haven't do any diagnostic yet, but yesterday my 500GB Seagate HDD passed SeaTools's (Seagate HDD's Diagnostic Tool) Short and Long Drive Self-Test.
Initially I plan to reformat everything and switching into AHCI mode. But since now that you mentioned no performance gain and in fact lower its performance, I hold it up at the moment and will do some HDD scanning. Perhaps any good applications to be recommended from you?

P/S: I'm running Windows XP Pro SP2