Basically, iv build up a computer, which went well. Wanted to wipe the hard drive clean and reinstall OS and relised the cd drive wasnt power, connected it up and now i get an error message asking to select a proper boot device, when i unplug the cd drive it runs fine again through the hdd. I have both the Cd drive and Hard drive on the same IDE cable if that helps, and my motherboard is an Asus M4A78LT-M LE is you wants the bios.