true ...

did you ever hear back from your friend at ASUS regarding the BIOS?
It appears that I've run into similar problems as yours. Earlier it was just the Shut Down issue, but now if I boot into Vista with any BIOS > 0803, I get BSOD shortly after. Only with BIOS 0803 is my system running stable & without issues. The BSOD's and reboots and freezes knocked out my system so bad that I'm having to format my drive & reinstall Vista later today.

I'm stuck on 0803 now (Won't even try going into anything higher), until they can issue a better BIOS for us Q9450 owners.