I've just completed a new rig. When the GPU is plugged in and I turn it on, the fans will run but the computer won't post at all. If I unplug the PCIe power, turn on the computer, then plug it back in it works fine, just using onboard graphics.
I thought this may be a driver issue, so I've tried several times to install CCC. This seems impossible, however, as every time it will extract all the files but the ATI Technologies folder will be empty, and no program was actually installed.
I've tried many different things regarding the drivers and it's making me tear my hair out
check that you have both the 24 pin and the 4/8 pin power connector connected to the mb. the video card need the right amount of power from the pci bus to work. have you tried moving the card to another pci video slot to see if it the slot or the card. have you checked that the pci video is the first video device in the bios. if it is all i can add it it could be a bad card or the power supply not outputting the correct voltage to power up the video card when loaded.