How old is the PC? PCI is a communication bus in your PC. Could be sound, video, modem or anything else that uses the PCI bus. It could be caused by the BIOS on your PC. I would go to the website of the PC manufacturer and download all the updated BIOS/Firmware drivers and upgrade. First, you may want to check their site for any tech help for Vista. If it’s home built go the the motherboard manufacture. I’ve did this a few times - I’ve used Intel boards and ASUS with good luck.
-Dan