Question : Problem: Computer shuts down abruptly

My new pc usually works but it just shuts down while I play games 3d intensive.
Not always, after a few minutes only with some games.
I thought it was temperature related but I checked, the only thing getting hotter is one of the 2 sli graphic cards but it doesn't reach the limit.
Once the pc even shut down with a game in background and just while I clicked the logging icon in the nvidia temp log program, and the video card was also quite cold.
As far as games go, it happened with serious sam 2 and trackmania nations.
I opened the case but this doesn't change anything since it's not the temperature.
I also checked fans and voltages, everything looks ok.
After it shuts down I have to switch it off from the power source and back on and wait a while before it is able to restart.

The abit mobo has a led with a code, the mobo is still on when it shuts down. The code is 8.2 when it shuts down.

Cables and connections are all good (including the video cards additional power plugs) or it wouldn't happen only with games.

This is my rig:

Enermax 600W Al055 Noisetaker Sli enabled
Athlon fx-60
2 512 Mb 7800gtx xxx edition from xfx
2 gb ram corsair
6 raid hard drives (4 maxtor diamondmax 10 250 gb sata2, 2 western digital raptor 36)
lg dvd writer
sound blaster x-fi
ABIT an8 32x mobo
Lian-Li Big Tower Silent 73slb

No overclocking!

Please I need urgent help.

Answer : Problem: Computer shuts down abruptly

If you disable SLI and remove one card can this error be reproduced?