Dude... better late than never....
I'm actually replying to your thread 20598 about ACPI issues... but for whatever reason, every time I try it tells me I'm not logged on... so maybe you'll get this msg...
When installing XP (fresh), installation detects ACPI functionality of the mobo/bios.
I understand that XP/2000 is a lot fussier about ACPI compliance than win98 ever was, so if not FULLY compliant, may get installed as a "Standard PC" HAL instead of ACPI HAL.
To check, under device manager, computer, yours probably says "Standard PC, not "Advanced Configuration and Power Interface (ACPI) PC"....
If so... bugger... you need to reinstall.
When install starts, and the message "Press F6 if you have a third party SCSI or RAID driver" appears, press F5... that's right, F5....not F6...
Choose a different HAL - you're after the ACPI one. Don't be duped by the menu that looks like you've only got two options... keep scrolling down and you'll see the one you're after.
Hope this helps and isn't too late!
Note - refer MS KB article 299340 for full detail.
Cheers,
Ben.