[newbe]

Hello! So,this is the problem.I just installed a second XFX GeForce 8800 GT Aplha Dog Edition(PV-T88P-YHD4).I made sure that everything is set up correctly ,all the cables pluged in, the SLI jumpers in the correct configuration ect.I updated...

Hello!

So,this is the problem.I just installed a second XFX GeForce 8800 GT Aplha Dog Edition(PV-T88P-YHD4).I made sure that everything is set up correctly ,all the cables pluged in, the SLI jumpers in the correct configuration ect.I updated to latest drivers and enabled SLI and PhysX GPU accelaration in the Nvidia control panel.The system works without any problems.But when I start Crysis ,the game starts loading and when the time comes to "click any button on the keyboard to continue" the whole system just shuts down as in powers off.Similar when I start COD 4.Here I manage to pick up the machine-gun at the beggining of the game and when I aproach the shooting range the system shuts off.I enabled the dual cards option in the game settings,but still.....
My system :
Intel Core 2 Quad 6600 2,4GHz,
RAM:Corsair 2 GB ,Patriot 1 GB,
HD:Seagate 250 GB SATA II ,Western Digital 640 GB SATA II,Western Digital 200 GB SATA II ,
PSU:750 W,( that's what the label says,but I think it's really somewhere around 600 W )
Motherboard: Gigabyte N650SLI-DS4L2 rev .1.0,
VGA :2 x XFX GeForce 8800 GT Alpha Dog Edition,
WinFast TV2000 XP RM,
Sony DVD RW AW-G170A,
Optiarc DVD AD-719S ,
Samsung SyncMaster 205BW LCD ,
...Win XP PRO Service Pack 3,Ubuntu
Could it be a power supply issue?Or maybe the fact that I changed the stock cooler on the first VGA (it's loud as hell ) but haven't done it yet with this second VGA (which is set up as the primary VGA ,in the first PCI-E slot,becausethe SLI bridge thingy could not fit otherwise...a huge heat-sink,Arctic Cooling Accelero S1 Rev. 2.. very little space avaliable,could barely fit it all in ..) and there is quite a difference between the temp. of VGAs ..one is at 60°C and the other at 45°C(this is where the huge heat-sink really pays off)...so maybe the system shuts down because it "notices" the difference as an anomaly ?This is just a wild guess ..I really don't have a clue what could be the problem...

..so what can I do?Should I reinstall the games or what(...hope not..there are a few on my PC..takes up a lot of time) ?...I don't want to give up on SLI either...

..and yes...before I installed the second VGA there were no problems...

..suggestions?