ISSUE WITH CRASHING

Hi everyone,

I just built my computer today, installed Vista Home Premium with only 2
problems. One, both my disk drives are defective, and the only is the one I
am typing to you guys right now.

After I installed Vista, I noticed something weird. My 8800GTX was rated as
a 1.0 on the scores table. I tried reintsllaing the drivers with no avail.
Still at a 1.0, I tried to refresh the hardware. The computer shuts off just
like I pressed the power switch.

The problem gets worse however.

I then tried to install Crysis, which worked, until I actually tried to
play. After the game fully loaded it tells you to "press any key to continue"
which will let you start the level. Immidietly after I press "any key to
continue" it shuts the same way it did when I tried to refresh the scores.

Any time I try to change the drivers, it doesn't work anymore, it tells me I
am using a 32 bit uninstaller and a 64 bit file.

Why does my computer keep crashing after I try to change the settings of it
or play a game?