I have a friend that has a Compaq computer with a AMD K6-2 300mhz processor. It has onboard video but he wanted to add a 3d card to it. He moved the jumper on the motherboard to disable the onboard video and put the GF4 420mx card in the first PCI slot. Unfortunately he has no video. I think the computer just locks up. What could be the problem? The specs on the card say minimum of 266mhz cpu. Thanks for your time and help.