2 beeps then error

This could be a few different issues. Please state whether it is 2 short beeps, 1 long and 1 short, or 1 short and 1 long, all of these are different errors. If it is 2 short beeps you should see an error code on screen(usually 3-5 digits).

If you dont see an error code it is most likely and AMI Bios error and if it is 2 short beeps your IBM has memory problems. If you have no video at all on screen you have a parity error in your first 64K of memory. First check your RAM. 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.