Theres only 2 reasons to change a bios. The first being that the board shipped with problems and only a updated bios fixes those problems. The second being, sometimes certain hardware reacts differently with bios. Like my dfi board for instance, the bios it shipped with would not run my ram overclocked in a 1t timming and stay stable. Don't ask i have no idea why, but i do know the updated bios does same settings and bam 24 hours mersienne prime/prime 95 stable. Go figure

Naw man, that mother board supports 16x16x8 pcie. as for throwin another 275 in sli i can tell you this sli is a tempermental beast and your gonna turn your box into a space heater. just consider the extra heat and if its not a big deal id say go for it. I'ts kinda fun having a multi card setup, albeit a pain sometimes.

You might wanna try msi afterburner. For some reason that program is soo spot on with the voltages. i used a meter to see how close it was and it hit +/-.02 within the voltage meter i had on the backside of a 480 we tested. really a spot on program.

Just take the plunge go get a xspc 120 radiator, laing d5 pump and micro rez. Just juice it. you know you want to. When its all said and done you wont have some ridiculous hunk of crap taking up way too much space.

1.Download "driver sweeper" from guru3d.com

2. uninstall your catalyst control drivers through control panel--->programs--->uninstall a program

3. reboot in safe mode [default f8 key on boot up]

4. run driver sweeper then reboot

5. install fresh drivers

Are you running msi afterburner? there was a little problem with those causing stuttering when using an ati card and remapping the fan through that program. The other idea that i had is check with a program called "gpu-z" and see if the card is accessing the required pci-e lanes it needs. I had a 4890 from xfx that ran like it was perfectly fine but stuttered with poor performance and found out that it was the card not accessing all the pci-e lanes it needed. Btw the memtest suggestion is a really good route too. Like you said you might be running it at its stock frequency but that doesnt mean that the board didnt mess up a latency setting thats causing it. asus boards are notorious for running tight auto settings on ram.

Have you tried uninstalling the drivers and cleaning out the drivers in safe mode then reinstalling?

To be honest man i can tell you right now that your proc is running way too high and its protocol on the motherboard to just cut power to save the cpu. Thats what I think it is. I dont know for certain so i suggested all that little stuff to do first just as a process of elimination. if you do all the little things and its still goin black then youll know for certain its the cpu overheating and shutting down

1.uninstall drivers

2. reboot in safe mode

3. run driver cleaner

4. reboot into regular windows

5.reinstall drivers

http://products.amd.com/en-us/DesktopCPUDetail.aspx?id=682. I've seen alot of people having this problem. The misconception is between the 2 latest revisions of the 955. You need to find out if your running a revision 2 [rb-c2] or a revision 3[rb-c3] the revision 2 had a higher temp threshold then the revision 3. Also in the meantime you might just wanna reinstall your drivers from scratch. uninstall from the control panel then reboot in safe mode and use driver cleaner from guru3d.com. Reboot. reinstall and see if the problem persists. Honestly your at redline on that processor you should not be getting that high. I also think you might not have seated the heatsink correctly.