Before I get told to search for answers, I already have, both through google, and through this site, none of the other solutions have really worked.

On just joining a server, my fps is fine. I have between 100 and 200 fps (sometimes more). However, given about 3 or 4 minutes, my framerate becomes somewhat jumpy. Movement sometimes brings it down to 30 or less, and breaking something brings it to 1 for a second or so. Even moving the camera rapidly in any direction can cause the frames to plummet. This is in fact rather new for me, as using this same computer a couple months ago with the client didn't have any such issue.

I can run the game perfectly well in a browser. In the client I can only do it if I set the view distance to tiny (which I suppose would make survival mode more intense, but that's not exactly what I'm playing the game for =p)

I did update to windows 7 ultimate not too long ago, and am wondering if there's some issue with that, as I was using Vista Business before.

My computer is a lenovo thinkpad t61p, core 2 duo 2.4 ghz processor, with 2gb of ram.

Tips? Ideas? Anything else you may need to help me troubleshoot?

Thanks a bunch