Trying to upgrade, running into problems

My original system :
System Manufacturer/Model Number E-4610D
OS What's your OS? Intel Core 2 4300 ( 1.80GHz 1.80GHz)
Motherboard E210882
Memory 2 x1 gigs DDR2
Graphics Card(s) Gefore 6600
Sound Card on board



So the deal is, my best friend brought me some goodies to put in my PC to upgrade it a bit.

He brought me a geforce 7800GT
4 x 1 Gig Sticks DDR2 ram
a little dual fan to put underneath the video card.
500w power supply


I installed all these things (except i only put 3 of the 4 gigs of ram in there, because otherwise the PC wouldn't turn on) and the PC seemed to run just fine for a while. Then suddenly the computer turned off. I turned it back on and checked the event viewer:


I had to keep turning on the PC to check some things and the problem kept happening. Although sometimes it took a while (2 hours or more) for it to happen just out of no where. I have Googled this event ID 41 and can't seem to figure out the problem exactly on my PC. Can anyone break this down for me because I'd really like to be able to upgrade this thing so i can play my games and do video editing for youtube etc.

So far the only trouble shooting i have done is:

trading around the memory sticks and / or removing 1: Didn't fix it
I tried without the dual fan under the vid card and oh jee i dont remember i have been working on this for a long time now.

I really need this to work i don't see why it wont work can someone help please.

The kernel error simply means the PC unexpectedly lost power, and is not exactly the cause for anything, or reason for alarm.
A simple power outage can cause the same error to be logged.

Sometimes, the error that occurs just before can show some insight as to the culprit however.
Try looking at events prior to the kernel power failure.

This almost sounds like a failing PSU if theres no sign of error or BSOD.