Before installing a new graphics card try another monitor to see if that might help. No need to buy 2 new things if one suffices. A monitor is easier to try than a graphics card.
Kees
So I've recently ran into a massive problem. I'll post my specs below so for now I'll run through everything that happened.
So one day, my screen randomly went black, the sound in my headphones jacked up and repeated the last 0.5 secs over and over again. I basically had to restart. Upon restarting, suddenly on boot, there were two thick vertical lines of white. One near the center of the screen and one to the far right. The computer was booting normally until the 'Starting Windows' with the window icon popped up, because after that the entire screen went black, there was no sound of reaching the login screen, and the computer was still running normally but the screen was completely black. So after a couple of restarts it works completely normal again. But only for a couple of hours, the same problem popped up and I did the same "ritual" to get it working again, but this time it only lasted for about three hours. And the next time it happened I simply couldn't get rid of the problem. I could go into safe mode without any issues, how ever there were small horizontal white lines across the screen, but it was working just fine. And I could also boot from disc, but I was not able to reverse to an earlier working version for some reason. So I clean installed the harddrive with windows again (I was already planning to do this anyways, so it didnt bother me). But during the entire installation, these two thick, white and vertical lines where in the screen, but the computer was working just fine. I get through installation, drivers for my motherboard etc.
Installing the GPU drivers, it asks me if I wanna increas my resolution during installation, I click yes. But for some reason, that was no the original 1980x1200 resolution I was using before so while it was installing I went in manually to check. And for some reason the highest available was only 1400 something. But I figure it was just during install so I just let it be for now. May I remind you that these two big white lines where still there.
The installation finishes and I reboot, this time when I go into resolution it still only maxes out at 1400 something. so I try it. The two vertical white lines splits up into 5 -6 ? and they look like really long barcodes across the screen. At this point I'm just utterly confused at whats going on. I figure to just try to reboot the computer if there was a configuration that wasnt made or something. And that's when it basically shot me back to square one. It boots up with two big, white vertical lines, and I cant get past the windows icon boot screen. As it just becomes a black screen and nothing happens.
I for the record have opened my case and blown out all dust etc, taken out my gpu from its slot and made sure it was clean etc.
I'm at a complete loss on what to do, this problem has never occured before, please help.
Specs:
AMD RadeonHD 6850
MSI B85M-E45
BallistX 4GBx2
i5 4460
XFX TS 850 80+ Bronze/Silver (cant remember which 80+)
Windows 7, 64 bit
If you wish I could try getting a recording of what the boot up looks like.

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