I recently rebuilt a P2 450 with Windows 2K. I added a new cd-rom drive, too. I was going to add more memory, too, so I took out the existing RAM to see what type I needed to buy. After I reinstalled the RAM, I was having trouble with the video card- it wasn't recognizing the card. It turned out that the video card came loose after I removed and re-installed the memory, so i removed the card and re-seated it. The machine would then boot up fine, but now it doesn't recognize my hard-drive. The machine was working fine after the initial rebuild, so I'm not sure why all of a sudden it won't recognize my hard-drive. I tried physically removing the HD and reconnected the cables, but it didn't work. I've checked all the cables connecting all drives to the MB, but everything is fine. I also tried re-installing the OS but it will still not recognize the HD. Any suggestions?