A few days ago I started getting some problems - my computer was crashing to the blue screen, telling me there was a hard drive problem. At first, this just occurred once randomly, but then it started crashing every TIME time I started up Windows and got to the desktop - within 30 seconds or so, it would crash and restart itself. It's gotten to the point where I simply get the SYSTEM BOOT FAILURE message and can't even get anywhere (also, sometimes it just hangs up and I don't get the message, and it just freezes up). To complicate things, I have two hard drives that were in a RAID 0 setup. I figured it might be a hard drive problem but the chances of both of them being out are pretty low. I tried utilizing ONE hard drive but BIOS doesn't seem to be picking them up, as there aren't any hard drives listed when I do so. I've deleted and remade the RAID setup, which will show up in the hard drive listing, but I still have the same problem. If I insert the Windows XP System Disc it is unable to install because the hard drive isn't detected. I'm also not completely sure, but nothing is showing up in the SATA drive listings in BIOS - I can't remember if this is where the hard drive is supposed to be (somewhat experienced but not enough.) The drives themselves function - they aren't completely dead and are running and spinning. I've disconnected a few cables when taking the drives out of where they're tucked away but it should be set up correctly. At this point I'm lost as to what the problem is - I've never had the computer unable to locate a hard drive. Any help would be much appreciated, hopefully this post isn't too confusing or lacking any info.This is what I would do. First I agree with your approach of using one HD only so that the problem solving is simplified. I would try a spare cable and boot to bios with just one HD and see if a HD appears. No point going any further if the bios does not identify the HD. If the new cable has same EFFECT as old then I'd get a spare HD and boot with that.

By doing this process of elimination you can hopefully narrow down to where the problem is.

Another suggestion I have is to use some compressed AIR to blow out dust etc. Computers accumulate so much fine gunge in them and sometimes a good clean can fix problems such as where there is a poor connection.