I built a computer and while I was carrying out a standard restart the power supply (450w) died with a loud pop and a flash! I purchased another power supply (500w) installed it, and it worked, which was a relief because it ment that the motherboard wasn't fried. However Windows would not start, and through the BIOS I was able to determine that the computer did not detect the HDD, or the CD-RW drive that was previosly installed. Worried, I removed both drives and then installed just the HDD with a new IDE cable. Luckly, this worked, and I preceeded to install the CD-RW drive. But now the system will not boot completely and I receive an error message, but the computer now detects both drives correctly (HDD is master CD-RW is Slave) Error is as follows:
NVIDIA Boot Agent 242.0535
© 2001-2005 NVIDIA Corp
© 1997-2000 Intel Corp
[then 10 seconds later]
PXE-E61: Media test failure, check cable
PXE-MOF: Exiting NVIDIA Boot Agent
Disk boot failure, insert system disk and press enter

Any Help would be greatly appreciated. If you need and specific spec of my computer, don't hesitate to ask .

First, you should not have the optical drive and the hard drive on the same IDE cable, that will greatly slow down file transfers. Off the top it sounds like your CD has been damaged. One bad drive on a cable can cause the other drive not to work or be seen by the BIOS. Try subbing another CD drive.