Updating the bios is always a possibility. I've got two other machines I'm running winxp on, and hibernating perfectly. Cusl2 and Asus p2b.
One solution that works is to hibernate and then throw the switch on the PSU at the back. That holds it till morning, when I throw the PSU switch back on and hit the case switch and start up just fine.
I think one morning i turned the PSU switch on and let it sit for 45 minute and it didn't start itself up... anyone getting a clue from that? I'm not.
BTW my PSU is a RAidMax 400W - i've seen it put down as a mediocre psu, but I'm quite happy at its stability. 3.3v line sits at 3.33v forever, the 12v line sits at 12.00v forever. Naturally the vcore is all over the place: goes from 1.49v-1.62v depending on load, but that's the mobo
thanks for your reply, i may upgrade the bios to see if that has any effect.