Now did that subject line catch your attention? Looks like Brian Burke, of nVidia is posting over at nVNews, asking for help from the community, about the shiverinig, quivering lines that some people are supposed to be having problems with. It seems to be happening in vVidia as well as ATi cards. I'm lucky I haven't experienced this problem. At any rate, if he finds the cause of the problem, I'm SURE he's going to share it with ATi. HeHe. I didn't read the whole thread, just the headlines here. Here's a quote from it.

it's got to be

monitor refresh rates..............those with inadequate capabilities in refresh rate ..............could ..........be faltering
ps............ole' one.............hl2 AA fixed........all cards