Hey guys.
Ok, my mate just blew a stupid amount of money on a new rig, which we put together a couple of weeks ago (top-notch components).
He started off with one XFX 6800 ultra, which was running like a beauty, but he was only getting around in 3dMark05, which he wasn't happy with, so the next day he ordered a second identical card.
We installed it, benchmarked it, got about 10.5k points in 3DMark05 this time round without any overclocking - lovely jubbly.
During the next few rounds of benchmarking, the screen started to get a sort of 'tearing' effect, as if the two cards were out of synch or something. We thought maybe it was just 3DMark being odd, but then Far Cry, and Painkiller developed the same issues.
And then we were hit by the BSOD! (Which was also illegible due to tearing.)
Rebooted, checked GPU core temps, everything was normal, but now the screen had started shimmering, and any activity caused the computer to hang, and then crash.
We took the cards out, blew in the PCI-E slots to dislodge any dust that might have settled in there, and swopped the cards over into their opposite slots (i.e. card 1 into slot 2, etc).
This time round, everything worked, but we still had a horrible shimmering on the desktop. We thought maybe it was a driver issue, so we DOWNGRADED from the very latest official drivers (76.4 or something I think) to 73, as reading some posts on here seemed to indicate these were the most stable for SLi.
Now, everything is fine, games run stupidly quick (although, even one 6800 ultra saw to that) and there is no evidence of tearing, shimmering, or artifacts.
The problem is, every now-and-then, while on the desktop, the screen will turn completely black, and there is no way to recover it. The monitor doesn't report a lost signal, but it's not displaying anything at all. The only way to recover from this is to reboot.
It's got us utterly stumped, and it's really annoying to have this amazing machine which is tainted by such a stupid problem.
Has anyone else experienced this?
Oh, and the mobo we're running is an Asus A8N-SLi.