I had a very similar problem like this... Turned out to be the drivers for the promise raid/ultra cards... the same thing happened on both of them... i think the ide bus would reset, which caused the whole system to freeze up completly for a sec and then work normally for another min or so before it happened again..
Spot on, freezes for a second and then runs fine. I wouldn't really care that much, but the audio stops for that second too!
My guess (and this is coming from someone who has a couple NT4 certs) is chipset drivers.
You didn't mention what chipset your mobo is, but certainly VIA *MUST* be running very recent 4-in-1 drivers. Most every person who says VIA chipsets are crap hasn't updated their drivers properly. They run like absolute dogsh!t until you download the latest versions. The driver CD that ships in the box is worthless, and the built-in Windows drivers cause all sorts of problems.
Intel chipsets aren't as fussy, but they SHOULD also be running Intel's drivers for your chipset, anyhow. I just trust Intel to know their own chipsets better than MS would.
Not sure how SiS is on drivers, because I've always avoided them.
