Hmm...funny you should mention that. I have a very similar problem...actually, the same problem. I only noticed it when I installed the new nvidia drivers (9th dec. 2003) but even before then I was having trouble running two clients...now it is impossible. I think 1.65 plays a part but those drivers are very suspect to me. Can't be arsed to uninstall them though because I have quit the game. I have the exact same gfx card as you as well.