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I'm really at the end of my wits on this one.

Installed the card and it seems to have passed the POST test (it is starting). What I did:

  • Uninstalled old drivers for Nvidia GeForce 2GB GT640.
  • Removed Nvidia GeForce 2GB GT640.
  • Inserted the new graphics card and and connected it to my monitor via HDMI.
  • Installed drivers for new card.
  • Restarted system.

This is when the problems started to show up:

  • When I boot up, everything is fine. The splash for my ASUS motherboard shows and then the Windows loading screen appears. I can access the boot options as well, by the way.
  • As soon as the Windows loading screen is finished, the screen goes blank and my monitor tells me that there is no HDMI signal. I tried DVI as well and the exact same thing happened.
  • If I turn the monitor on and off and change the input a few times, the display will show up at the proper resolution for a moment and then it will go black again. The display will continue to blink like this... displaying and going black. The monitor shows a blue light throughout all of this, so it doesn't seem to be a power issue.
  • I can boot into Safe Mode - what I'm in now. However, I have noticed that horizontal red lines will flicker across the middle of the screen every few seconds or so.

To fix this, I've tried uninstalling the drivers, wiping them and even cleaning them from my registry afterwards with CCleaner. The result remains the same, regardless of what input I'm using.

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The strange behaviour in Safe Mode suggests that the GPU itself might be broken in higher display modes. If you can test it with another monitor that would help you diagnose the issue. – mprill Dec 25 '12 at 17:45
@mprill Hi, sorry, what do you mean by broken in higher display modes? – user182538 Dec 25 '12 at 17:54
When your computer starts the BIOS initializes the video card's BIOS to perform the basic video functions - drawing the text listing hardware, for example. This primitive video mode is only used until an operating system's own video drivers initialize said video card's higher functions to display resolutions better than VGA. BIOS is usually limited to 640x480 with a 4bit colour space. What I mean is that your GPU might be broken, physically damaged maybe, when it gets initialized by Windows' drivers. To eliminate the unlikely scenario in which your monitor is at fault test it with another one. – mprill Dec 25 '12 at 18:03

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