I changed the IRQ setting for the USB device from 11 to 6 through the BIOS settings on an old COMPAQ deskpro using Windows 95. The system would not boot after that, but would beep several times. I tried to clear the CMOS by removing the battery as well as the jumper, but this did not work. The problem was resolved by a technician, but I am interested to know how this error can be resolved. The IRQ 11 was shared by the onboard video, USB and the network card.