Hello. I'm received my new Vista Ultimate SW and am trying to do a clean install on my new home build machine. it's got 2Gg RAM, DUo Core processor and 400Gg HD, PCIe Sapphire 1650Pro graphics card....however.... - During the install when the DVD copies it's files, the system randomly powers off without notice. This has happened at 59%, 62%, 74%, 84% - then when all sw has been copied onto HD, and the installer moves on to try and install features and packages, the system then switches off again. The RAM, the processor and the motherboard are all brand new and reputable brands. The power supply (400W and also new) has been swapped with my old one 300W, but the same thing keeps happening. I've unplugged all unneccessary PCI cards etc (to take it down to a barebone system). The BIOS safe defaults have also been chosen. It seems to me its a power supply problem, but thenagain I've tried 2 different ones and am getting the same results. Before you ask, I've tried using different SATA drives as the install target too... anyone have any ideas on whats going on? at the moment i can't get my new software installed on the **** machine. is it the power supply not feeding enough power through to the mainboard ? is the pcie card zapping too much power ?!? HHHHheeeeeeelp !!