Sometimes when playing games, the gameplay goes from completely smooth to utterly unplayable. I often have this with TrackMania Nations Forever and just noticed the same with Left 4 Dead 2. It could be the graphics settings, but I doubt that mainly because: It doesn’t seem to have anything to do with what scene or track I’m currently in. At one time a track plays fine, the next second the game is suddenly crawling along at two frames per second. Almost literally. I tried lowering the graphics settings to a much lower level in TrackMania, but that didn’t seem to matter. The slowdowns were still there. I have a stock 13-inch MacBook Pro. 2 GB RAM, nVidia 9400M graphics. The games run on a recently purchased copy of Windows 7 Home Premium, but the problem also existed while I was still using the release candidate. Some notes: Half Life 2 plays absolutely fine. Portal had a few slowdowns like those in TrackMania but I didn’t play it long enough to say for sure. Rebooting is the only reliable fix. The laptop does not seem to be exceptionally hot. Not more so than after a session of HD trailer watching. Did anyone else here have a similar problem before? Any ideas on diagnosing or resolving this? I thought about adding RAM but I’m not sure.