HP Vectra VL.6/266.SERIES.6.DT

Power PC up, no display on monitor (tried a few monitors). PC then beeps twice after being powered on for about 30 seconds. Have tried CLEAR CMOS and will now try steps for "2 beeps" BIOS beep code troubleshooting:

Your computer has memory problems. First check video. If video is working, you'll see an error message. If not, you have a parity error in your first 64K of memory. First check your SIMM's. Reseat them and reboot. If this doesn't do it, the memory chips may be bad. You can try switching the first and second banks memory chips. First banks are the memory banks that your CPU finds its first 64K of base memory in. You'll need to consult your manual to see which bank is first. If all your memory tests good, you probably need to buy another motherboard.

any other ideas?