So about 4 years ago, I bought this HP computer and modified it a bit (new sound card, video card, power supply) and has been working very well ever since. But all of a sudden, all my PCI slots decided not to work. My sound card (Sound Blaster Audigy 2 ZS) and my network card are not working anymore no matter what slot I put them in. I've tried going in the device manager, uninstalling them and re-installing them. It recognizes them and installs them, but they just don't work. They have a "!" in front of them.
Does anyone have any suggestions as to the steps I should take to try to fix this matter?