Wide World of Women

I have has a few times in the past month where the computer tower has shut off.
The monitor stays on and the rest of the house's electricity stays on but the tower shuts off
I have gotten a new power supply and a new processor fan but it happened again last night...
Is there a reason for this random shutdown of the tower?

It could be a zillion thing! but the psu is always the usual suspect, graphic cards requires 550 watt or above..i'm assuming you've got that covered?
mine requires 550, but i installed a 650 to be on the safe side..
also it might be helpful to check your event viewer for errors..
I remember once my system started shutting down for no reason whatsoever!! I went crazy and it turned out that a software i previously uninstalled 'called online armor' was the reason!
anyway, check your event viewer..and next time when it happened, remember what application/s was running before the crash.
good luck.