Running Vista Ultimate 64bit updated with Vista Service Pack 1 Release Candidate 1 - CPU Quad Q6600 - card 8800 GTS 320MB ( driver v169.21 ) - 4 GB RAM - ... i can play for hours and hours without crashing. Crashes only occured, when i took out the game DVD, then i got game crashes , for example, right after saving ! Since then i leave the DVD in the drive and no problems anymore. So it can't be really only Vista producing problems on certain systems ...