Gigabyte 4850 stopped working

I've got a:
- AMD P2 X4 955
- 4 gigs of ram ddr3
- 500gb hard drive
- Gigabyte 4850 1GB ddr3 passive/fanless

To bore you with the story; i bought it early july this year and it had been working quite well, running games such as Crysis, Far Cry, COD4, Fallout 3, Borderlands, Sims 3, left 4 dead yadadada. But recently (i mean yesterday) i was playing the SAW game (*shrugs*) and i was about 20 minutes in when my system just shut down. It seemed like it just lost power. So i turned it back on and 1 long beep followed by 2 short ones occured during start up. My Monitor didn't work but i could hear the windows start up on the sound.

I then checked the net and saw that the beeps mean somethings wrong with my graphics card. I've never tried to OC it, or fiddle with it any other way then installing updates for it. It strikes me as odd because out of all the games; SAW was the one to f*ck it up. I'm not sure what to do right now, but i'm going to send my system in to the guys who i bought it from. But is there anything else i could do?

Thanks in advance.

Nope it was running normal, normal conditions and no bumps. I checked the RAM sockets seem to be OK, tried pulling them out and putting them back in, no luck.

I'm pretty sure it's not the PSU, it seemed to be running ok for a good couple of months. I've tried plugging it into different sockets, no luck there either. Seagate SS 550HT? i think that's it, it's what it says on the box.