Overclock stable in XP but not Vista?

Yes, interesting I know. Before upgrading to Vista Ultimate a few months back I had tweaked my system to be 100% prime stable under XP. I have an E6600 overclocked to 3.42ghz. I was able to run iTAT full load overnight as well without any issues.

Now, Vista has been working fine. I have not had any crashes or anything of the sort even when playing hardcore games. However, I finally got around to downloading iTAT and my idle temps are almost 10 degrees higher than they were in XP. Under full iTAT load the system will blue screen and restart. I upped the vcore voltage to 1.4 but that is as high as I would go. It would still blue screen under iTAT. I also eventually got an error while running orthos.

Anybody have any ideas how a rock stable overclock on one OS could be not so stable on another? During regular use and gaming the computer is fine so that is why I didn't even notice it so it is not that big of a deal. Games and whatever else I do regularly do not even come close to the orthos or iTAT load and I never have crashes. But that is not the point. Anybody else have similar issues? Thanks.

i had a similar issue like yours. ocing my cpu could go higher in win2000 and then when i got xp i had to bump it down 200mhz just to get it to load windows. kinda wierd. i didnt really fix it but when i got my second gig of ram(old system btw, not the one in sig) it allowed me to go above and beyond what i could before. dont know, it was kinda wierd

i remember back in the 3D mark 2001 race for 20k, every bencher benched on windows 2000 cus it allowed for a higher cpu overclock than XP did. Maybe it's the same for xp to vista. XP allowing a higher overclock than vista.