I recently purchased a new Western Digital ATA100 hard drive for my old PIII 550mhz computer. It works great, but I could only reach UDMA 2 instead of 5. So I purchased a Promise Ultra ATA100 TX2 controller card. I installed the drivers, changed by BIOS settings to boot a bootable add-in card first, saved and shut down. I connected my cable to the card and rebooted, everything was fine and the card recognized my drive, but then went blank and posted the message that NTLDR is missing. If I connect my cable back to the motherboard I can boot just fine. Any idea what is causing this? Thanks.