I have had this problem both with 8.04 and 9.04 / with 1.0.1 and 1.1.29 i have intel celeron 3.33ghz radeon express 200 onboard ati graphics I install steam which has a wierd thing of scrolling down and right staying there so i must install games threw the actual website i downloaded the portal demo and here is what happened on 8.04: Launch options= -dxlevel 81 (to load intro screen with options) in the containment area while game countsdown and computer talks game runs smooth until the final 3 2 1 then i get a gray screen that get lighter and darker as i move.. i managed to find the next room where i put the cube on the button to get out but when i get to the next part to jump onto the floor the second i hit the floor i get the same gray shadey glitch.. i tryed the no clip command and skipped this part went on to the elevator again went up and the second i stepped out the elevator again.. gray shadey screen... ok so i updated to 9.04 and upgraded wine: using no launch option (game started normal just a little choppey) now the game starts chopped but i can handle that.. but again the same issue with as soon as the countdown ends i get the gray shadey screen... i tryed again to try to find the door but no luck this time plus with my frustration i gave up sooner than before.. but yet both had the same exact glitch... what or how can i fix this.. i want to buy the game but if i cant even play the demo i dont want to waist the money and im reluctant to try playing games on ubuntu.. i do not have nor own windows so ubuntu is my only option. any help is greatly appreciated!!!!!!!!!! ~~~<3~*Always~DPK~~~