There are other threads about 3rd party screensaver problems in SL. But I'm having trouble with SL's own built-in screensaver. An hour after installing SL, I came to find a black screen, and endless beachball spinning and no hope of waking the machine up. Forced restart. Got into Sys Prefs > Desktop & screen saver > Screensaver. Tried to select an item in the list. Back to beachballing and Sys Prefs maxing out the CPU. Finally managed to find a way to disable the screensaver entirely. Is anyone else getting this? Does it have anything to do with the 64-bit / 32-bit thing? (Sorry - I'm not very geeky) Any ideas? Thanks.