I have 2 6970s running a dual monitor setup, I've had this for a long time and it's been working fine when I just extend the displays. I wanted to duplicate them when I watched a movie or something, so I went into the Screen Resolution in the control panel, (accessed via right click menu on the desktop) and changed it to "Duplicate these displays", when I first did this, I was running the screens perfectly well with both plugged into the DVI ports on 1 card. The screens went black and flashed a few times, before bluescreening and inevitably NOT reverting the display settings. Now, when I launched the PC, I would be fine up until I loaded windows, on the login screen, there was artifacting and weird graphical errors everywhere, but I managed to login, when I logged in both screens lit up and the PC crashed as it did before. So, I tried running just 1 monitor and it worked just fine, but when you run 1 monitor you cannot set what the computer should do if it were to detect another, so when the other is plugged in, the same crash ensues. I eventually got around this by plugging one monitor into the HDMI, and another into 1 specific DVI port (when it was in the other one it would refuse to extend the displays, with the error: "unable to save display settings"). But now with this botched semi-working mess I tried to duplicate them again, this time I had learn't if it messed up I could press "ENTER" to click revert, which I wouldn't be able to see. This didn't work, the computer crashed, but I couldn't see it crashing since the monitors were telling me they were: "unable to display this video mode, change display input to 1080 x 1920". I assume it was the same blue screen error. Now when I loaded the pc up I had all the same problems as before, the crashing, the artifacting, the same issues. I am currently coping with just 1 monitor right now as I type this. I know this is specific but please help.
Things I've tried: Unistalling then reinstalling latest official drivers, crying, trying to change the display settings in safe mode (doesn't show multi-monitor options), resetting BIOS <- I was desperate at this point, and trying to change it without drivers installed, which again just didn't show any options, taking out one of the cards (made no change).
FULL SYSTEM SPECIFICATIONS:
FX 8350 OC @ 4.7ghz, Corsair h100i for cooling, Stable.
2x VTX HD 6970 at stock clocks.
Asus M5a97 r2
Novatech 850 modular PSU 80+ Bronze
16gb Corsair XMS3 1600mhz
Ask for specifics.