Help needed w/Monster Fusion AGP card

My setup is a Compaq Deskpro 6000 with a PCI Matrox card that I want to replace with a Diamond Multimedia Monster Fusion AGP – I installed the AGP card and installed the latest drivers & Win98 sees it fine as the secondary Display. As soon as I remove my PCI card and power back on I get no video with one long beep and two short beeps. I also have updated my system BIOS to the latest revision. Any help is greatly appreciated.