I get something similar:
Windows Vista Home Premium running on an ASUS P4P800-X 1g of ram won't hibernate when it set up to and I force it (button on keyboard) it resumes windows right away and then takes 2 minutes( I times it) Playing with the hard drive. It's consistant I tried it a few times.
The whole thing works perfectly well with XP.
My computer successfully goes into Hibernation with Vista Ultimate, but about 3 seconds later, turns itself back on and recovers fine. No yellow exclamation points in device manager.
Asus P5AD2-E Premium
2 gigs of Ram
P4 3.4GHz
ATI All-in-Wonder X600 Pro PCI-E
Using audio built into motherboard
Using built in networking on motherboard
No other PCI or PCI-E cards

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