My computer shuts down when its trying to load windows. It can sit in bios forever but when it loads windows it turns off. It lasts a few seconds. I have checked both my temperature (stays around 40-47 Celsius) and voltage(normal). I have also replaced the hard drive with the same result I have checked and have pretty much no thermal paste. Could this be it? the temps seem normal so I'm at a loss.
Frist, Please post version of windows and some information on your PC (make/model or what parts, how old, when last time it worked, etc.)
Then make sure you have removed all the USB devices from your system other than keyboard and mouse (no external drives, thumb drives, touchpads, printers, mp3s, etc.). Then make sure there is no CD/DVD in the optical drive. Can you boot now?
If the system still hangs download a bootable diagnostic. Something like "ultimate boot CD" (google it) see if you can get your system to load. If so run the HW diagnostics, especially memory diagnostics. If these are all clean then download and boot a stand alone anti-virus like norten. If that is clean look at using a Windows repair CD to see of you can repair windows.