Please calrify, is your drive not detected at all, or is it not detected at full 200gb capacity? If latter, you have couple of options. First off, ata 66 controller will not recognize drives capacity past 137gb which is a known issue. You can either try and upgrade your mobo BIOS, or partition your drive to say 2x100gb.
If your drive is not recognized at all, check the BIOS to see if it's been detected. Check your jumper settings, if it suppose to be your bootable drive make sure that it's on your primary IDE channel and set as a master.