Hi All,
First I was having issues with my computer locking up during screensaver activation. I have MCE2005 and I use the Aquarium screen saver. I disabled the screensaver and now it doesn't lock up. BUT whenever I go to play a game, it will make it through the loadup screens then gets into the first part of the game, then three or four seconds into it..BAM...it locks up. My hardware lineup is as follows:

Athlon64 X2 3800+
Asus A8N-SLI Premium
2GB Corsair XMS Pro PC3200 Memory
ATI AIW X1800XL Video Card
SB X-Fi Xtreme Music Sound Card
WD Caviar SE16 250GB HD
(2) WD Caviar SE16 400GB HD in Striped Array
Plextor 716SA DVD-RW Drive
Antec NeoPower 480
Powercolor Theater 550 Tuner Card

The lock ups occuring once some sort of relatively intense graphic activity occured leads me to believe it is temp related but I am running a watercooled setup and my temps are fine (under load CPU runs around 42C and GPU runs around 55C). I know these sound kind of high for watercooled but I am running a single 80mm radiator and fan. I know this particular card is sort of a power hog so I was thinking two things. Either it is the power supply (although great, maybe not the best for this setup), or I need to plug a molex into the EZ-Plug on my motherboard. The manual states this is pretty much for SLI setups but maybe this card is too much for no EZ-plug assitance even only on one slot. The two games I am trying to run this on are Star Wars: Empire at War and Battle for Middle Earth 2. I don't think that matters since it was locking up on the screensaver before it was disabled but may have something to do with it. Let me know any opinions or steps I should take.

Or could it just be that the specifically SLI motherboard doesn't like a non-SLI non-nVidia video card?

Seriously? No responses or advice?