I am having trouble with changing the gpu on my computer, i have a h8-1234 from hp and it has no on-board video, it came with an hd 7450 i believe and i tried to install a hd 7750, i also have a 600W power supply to replace too. the new power supply works great and boots the system with the old card but when the computer has the 7750 in there it just wont start up at all, no lights light up and fans turn on and when it does turn on the only thing i get is a black screen and nothing more. i did some research on the internet about this problem and found nothing to solve it. after a while i figured out a way to turn it on and that is by taking out the battery on the motherboard and plugging it back in after a while and the computer starts up nice and smooth and i can shutdown and restart with no problems at all since it boots back up with no problems. it would be great if it stayed like this but it doesn't, if the power cable that connects to the back of the power supply gets unplugged or the power in my house goes out its back to the same beginning and the only solution is to open the computer up again and take out the battery and put it back in and close the computer once more since the computer wont turn on at all or it has a black screen. i can manage like this but i still want to fix this permanently. does anyone have the same problem or similar? and have you guys found a way to fix this because it is kinda bothering me a bit now.
the new power supply (well new to this computer) is SeaSonic M12 SS-600HM 600W ATX12V V2.3
Oh, the new card works. I missed that by reading too quickly, I guess. In that case, I would begin to suspect the PSU. But it is strange the old card doesn't affect it the way the new card does. They are almost identical cards (as far as the system is concerned) except for amp draw on the +12V rail. When you say that the loss of power to the System causes the issue, that would tend indicate a failing PSU; possibly capacitor(s) going bad. But it's strange that the old card doesn't affect it the same way. (??)