The title says almost all but several more things to add. I installed another hard drive and everything was fine until I turned the computer off. When I turned it back on, no hard drive detected in bios again. The hdd's still spin up, but cannot be detected by mobo. Checked power supply while running and all is okay. The mobo is a p4b533-v that my brother was having trouble getting started. I had it working good for about a month and then, well, here I am. Any suggestions on locating the problem would be greatly appreciated.