Computer Shuts down when playing current gen games.

I have a ASUS CM1831 (https://www.asus.com/Desktops/CM1831/)

I upgraded the rig with a V600 600 watt power supply by coolmax (http://www.newegg.com/Product/Product.a ... 6817159079)

I then purchased a Nvdia GTX660 (http://www.newegg.com/Product/Product.a ... 6814130825)

Before the GTX I was using an older geforce 6800gts.

Everything worked fine until I recently when I tired to play current generation games: Assassins Creed 3 and Planetside 2.

At first I thought it was the crappy PSU so I just bought a TX750 Corsair.

I thought it could be a VGA issue so I swapped the card with Warning, who has the identical video card. The hard shutdowns no longer happens, but the video card/open GL would become unresponsive the game crashes (so does explore)

I performed a memory test, and everything is fine. FurMark exam crashes a few times but on other occasions it would last 20 mins without issues. All the drivers and bios are up to date as far as I can tell.

Could this a motherboard issue?

Here are some pictures:

Looks like a faulty video card. Maybe you got a bad egg.

what drivers are you using

I updated all the drivers on the nvida website.

Earl: I have 2 of the same Video Cards: one for warning and one for myself, both cards presented different issues.

I'm a tad confused on that part. Unless I have two bad lemons.

Well, if it's not the PSU or Video card, and it's not a software problem, then that leaves the motherboard....

Well, if it's not the PSU or Video card, and it's not a software problem, then that leaves the motherboard....

pebkac?

well if the cards work in another system and not your and with the changes you made it's either a mobo issue or something in the OS which at that point might be easier to format and do a fresh install of the OS

Update: Pretty sure it's a mobo issue since the card works fine on other computers.

thinking about buying this.

MSI 990FXA-GD80 V2 AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Product.a ... 6813130649

new egg is giving away a free 8 bg Crucial Ballistix Sport 8GB 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Low Profile Desktop Memory Model BLS8G3D1609ES2LX0 (value:$64.99)

reviews are good and it appears to fit everything that the CM1831 currently have. also be nice that the rig will have 16 gig of ram

just want to check it with you guys before making the purchase since i can't return it.