OK so I am a bit confused here. Upon trying to boot in Leopard my mac pro will get the the gray loading screen with the "loading circle" and just sit there forever. Than after a bit it will just stop and the whole computer can shut itself down. I just installed the 8800gt upgrade kit last week, and have had no problems at all for the past week. The only thing that changed that may be related is the 8800GT XP Driver. I installed the latest beta driver for it under XP in boot camp because it wasn't working properly with the default boot camp drivers. So I can correctly boot in the XP via boot camp, but trying to boot in Leopard it just hangs at the gray loading screen. Can anyone help me out here please. XP is fine for the occassional game, but I don't want to be stuck here forvever!