Ric, I would also check your drivers as well. I have my main runtime on an external drive, so I have it setup usng the Multiple runtimes features. I have had no problems with it at all. Then again my poser rig is a Laptop with a Celeron 2.8 ghz processor, 768 mb ram, Win Xp Home SP2 and an ATI Mobility Radeon 9000 video card.