Hello everybody. This is a long story, I'll try to be as clear and concise as possible: In September, I move pc to other room to paint my walls, in the process I clean it up, when I put it back the card doesn't post anymore no matter what. I stick with hd 3000 graphics until I figure out what to do. After lots of testing which included trying other video cards and have my 6870 tested somewhere else, I assume it's either the motherboard pci-e slot or the power supply. Since I had never overclocked my 2500k I say "why not" and move from my old Asrock H61 mobo to an Asus Z77-A, all while also replacing my older ms-tech modular psu with a Thermaltake Berlin 630. Same result as before, with one small difference, which is my lower PCI-E slot (x4) works flawlessly, whereas the main one won't work with drivers installed (tried 14.9 and 14.4). Recently, after over a month since I gave up, I tried seating the card back in slot 1 and it worked, it gave me video signal on both monitors, except it only did in VGA mode, as soon as windows updated drivers and asked me to reboot, it stopped outputting signal again, monitor in stand-by and all. Now, for the list of things I tried: other cards (all showed similar symptoms, working with no drivers), breadboarding before and after reinstalling my cpu with heatsink, one stick of ram, resetting the cmos, reinstalling windows, updating the bios, forcing bios to go with pci-e, disabling integrated graphics, wiping out drivers completely and installing other ones. The only thing I haven't tried is formatting and making a completely new windows install, ever since I replaced the motherboard I've always only done upgrade installs. I read this is quite a common issue with amd cards, could it be a bug with some settings in my card I do not know? I really have no clue. At this point I can't even rma my mobo that easily, I was so much of a jack*** that I picked the one model which was getting discontinued soon, and right now it likely is, rmaing it would take me months. OT: In the worst case scenario, is there a significant loss of power for a 6870 going from x16 to x4? Passmark isn't all that clear on the results. Thank you, for any further clarification I'm available.
If changing motherboards you should definitely do a fresh install. It might not be your issue, but it's a good idea nonetheless.
It still leaves me flabbergasted that the second slot eats the drivers and produces graphics like usual (stressed it, no problem, temperatures in order) while as soon as I throw the same exact drivers at the slot 1 it goes dead.
