when i have some heavy object in scene, and then i wanna render the scene, suddenly pops out of the 3ds window! and every thing unloads from the RAM! i have 4 GB of RAM. when it loades around 1.5 GB for 3dsmax.exe, it suddenly pops out. what can i do? i`ve just tried 9 version and 2008 version on XP and Vista O.S!