Back in the days of DOS, you had to manually set IRQs (Interrupt Requests) for your devices via jumpers. Of course, you also followed simple rules like never let your video card, network card, or sound card share the same IRQ. Even though PnP was meant to address IRQ deficiencies and allow multiple devices to share IRQs, I find that it is still essential that these basic statements hold true. For example, my 8800GT was sharing the same IRQ as my network card, so I got extremely bad graphic tearing in World of Warcraft and graphic stuttering in Call of Duty: World at War. OK, so I turn off my serial and parallel port to free up those IRQs and even pull out the video card and disable the network card to see if it will reassign the freed up IRQs to one of those two when they are reinserted and reactivated. No luck as they still had the same IRQs. In the end, I had to set my motherboard to run both PCIE-16 slots to run in 8x mode and put the video card into the 2nd slot. I remember there used to be some motherboards where you could assign an IRQ to a certain slot and I wonder why more motherboard manufacturers don't do that if it is still possible. It's frustrating to have to juggle cards around to try and get non conflicting IRQs so your system functions as it should.