Hi guys, fairly complicated problem here.
First up: OS: Windows 7 CPU: Intel i7 3930k GPU: Asus Radeon 7870 Mobo: Gigabyte X79-UD3
I figure those are the only relevant parts for this but can post the rest if required
A few days ago while playing a game, my PC suddenly froze and just gave me a bunch of vertical lines/colours covering the entire screen (as a side note, I had a similar thing happen years back with an older card where it was just overheating).
Upon restarting my PC, my login screen looked like this: http://i.imgur.com/NB2I5P0.jpg (apologies for bad photo, cut out username because it's my full name.)
After logging in, I immediately got the same vertical lines issue again and can't do anything except restart.
I assumed my graphics card was just dead, but I took it out and put it in my brother's PC and it runs completely fine. So, I then assumed my motherboard was the fault and tried a different card in it, and the other card also works completely fine. As a side note, I could get into Safe Mode with my 7870 no problem.
Next I tried updating drivers, no change, so I then downloaded Display Driver Uninstaller (http://www.guru3d.com/files-details/display-driver-uninstaller-download.html).
This allowed me to log in without any issues finally, however under Device Manager my card no longer shows up and instead reads "Standard VGA Graphics Adapter" which I believe is the onboard graphics.
Updating my drivers at this point causes the card to register again, however if I restart, after getting to the 'Loading Windows...' screen, I simply get a black screen that lasts forever instead of the login screen. At this point, I am lost for ideas. Safe mode always works, the much older card I've been testing with always works (4850 or 70 I believe) but I have no idea how to properly get my 7870 to start up.
One possibility I can think of is that my power supply is rated slightly lower than the recommended for the 7870, (450w PSU versus 500w recommended for the card).
Thank you if you've read this far, any help or suggestions are greatly appreciated, I'm trying to avoid formatting if at all possible, as having to redownload all of my stuff will be a pain (hooray Australian data caps). If you have any questions or need additional info I'll check this thread as much as possible.
For a briefer summary:
Starting PC with 7870 + drivers = Blackscreen where login screen should be
Starting PC with 7870 and all drivers removed = Device Manager lists "Standard VGA Graphics Adapter" instead, card is not active.
7870 works with no issues in other PCs.
4870 works with no issues in my PC.