I am trying the beta on my old laptop and I have a strange bug. The screen-shot explains it better than I can. I tried changing all the settings and its still the same. Sometimes when the screen-saver just starts, the rest of the screen appears for a split second then disappears again. I used to have version 2.6 on this computer and it ran without problems.
My computer is a Toshiba Satellite 1805-S204 with Windows XP, 512MB of RAM, Trident CyberBlade XP Ai1, 1024 x 768 x 32 resolution.