Can be anything... really... If hardware acceleretion fixed it, probably you could make an update... but maybe the card simply overheated... My poser 6 did fancy things yesterday btw... when i tried to run python 'delete all lights', my whole scene turned grey, and stayed grey... I had to close, and reopen... revert would not work.. I figure poser is a quite sensitive program, dependng very much on the platform and harware you use it with.. Many of you say you use athlons and 'round 1 gigs of memory... I have the same, and a pci-e card... still I have very-very long renders and unexpected crashes...