I recently purchased an HP with 4GB ram and 250 GB memory, i put windows vista ultimate on it hoping that it would keep me away from the problems when downloading archicad 12, and everything was going well until i tried to view in 3D and it renders for about five minutes, and then the drawing space is just gray, and you cant see anything, but if i click where the building "should be" it highlights (the green and nodes) and thats it. any suggestions???? anyone else going through this? please help!!! thankyou!!