Nevermind,
I figured it out.
The 64-bit Vista ultimate install went great, and since I'm the type who doesn't fix what ain't broke, I was happy.
BUT, as it turns out, the uGuru utility will not work with the default drivers installed by Vista (no matter how happy I was with them). After I installed the drivers supplied by abit's CD, and then installed the uGuru version they supplied on the CD, everything worked fine.
So, that's that. It's all good.