Hi A while back my motherboard began to die on me. One of the first things to happen was my main C drive wasn't being recognized. I had to dust off and old PATA drive that I had and use it to run my computer. I finally replaced the motherboard and bought a new SATA drive at Fry's while I was at it because the price was so good (640GB Seagate for $79). I got it hooked up but I don't think I installed it correctly. I've been running everything from the new drive for a couple of weeks now but had left the other drive installed so I could copy some files. It uses a different port on the mobo anyway. I finally decided I can take that old PATA drive out altogether and put it back on the shelf. But when I unhooked it and restarted my computer it wouldn't boot up. It said something like "bootmgr missing, press ctrl alt del to restart". The reason I say "something like" is because the words are not fully visible on my monitor - the first few letters are outside the frame. I had to shut it back off and hook the old drive back up to get it to start. So what does this mean? If I can run my computer on my new drive (which is set to C: and is set up as the first boot device in CMOS) then why won't it boot without the old drive hooked up?