just had the same bug on the MoE server... sound crackles, screen stands for a fraction of a second. lots of them.
At one point I had a big one which lasted like 2 seconds, screen was not being updated for that time as well. found myself in the wall.
Hardware:
Opteron 170
1024MB RAM
Geforce 6600 GT AGP
on-board 5.1 sound (Realtek 97 audio driver)
Hardware is ok, I'm not experiencing problems with anything else.