Need Help With Error - Unmountable Boot Volume

I got the "Unmountable Boot Volume" error for the first time today. Computer won't boot up in normal or safe mode. Have also tried using the recovery console as recommended on microsoft support and on many websites and forums, but I get an error after pressing R in windows setup that says "Setup did not find any hard disk drives installed in your computer. Make sure any hard disk drives are powered on and properly connected to your computer, and that any disk-related hardware configuration is correct. This may involve running a manufacturer-supplied diagnostic or setup program."

Does this mean I have to completely reinstall XP or are there any other options?

Reset the BIOS to defaults. That's the first thing to try.

I just reset BIOS to defaults and it didn't work, still get to error screen after booting in safe mode.

There are a few other things that you can try, no necessarily in the following order

Download the HD diagnostic tools from the manufacturers web site, burn them to a CD & boot the machine with it. Run the tools.

Do the same with Qparted. See if it even recognizes the partition.

Remove the HD & install it in another PC. See if it boots.

Remove the HD, mount it in a USB external HD enclosure, connect it to another PC, backup all you files, put it back in the PC & try to reinstall.

I ran the diagnostic tool and it failed to recognize the hard drive. Don't have a external HD enclosure and don't have access to another computer to install this in so I just bought a new HD and installed. Computer booted to Windows setup screen and when I tried to install Windows XP I got the same error message as before: "Setup did not find any hard disk drives installed in your computer. Make sure any hard disk drives are powered on and properly connected to your computer, and that any disk-related hardware configuration is correct. This may involve running a manufacturer-supplied diagnostic or setup program."
But after that I can't even get the computer to turn on. After hitting power button there is a loud noise, sounds like the fan but maybe the hard drive, and then it turns itself off.

Any advice from here? Could it be as simple as a bad cable or is there more going on?

Open the box, remove the HD, turn on the PC. Do you at least see the POST? Are both fans turning? Try to locate the noise if it's still there.

Stepping back to troubleshooting 101 have you tried a new IDE cable yet? To answer your question it could be as simple as the cable.

I suppose the other question is the drive ATA or SATA? If SATA are the drivers installed correctly?

Turned the PC on w/ HD disconnected and the auxiliary fan (Nidec Beta V) turns on super fast and loud and the PC turns off. The power supply fan turns on like normal. PC never boots to see the POST.

And it is a SATA hard drive, and I have power and signal cables attached correctly. I have not replaced the signal cable yet but will buy one and replace tonight to test.

There are only a few moving parts. Can you locate the noise. There are 2 or 3 fans, a HD & a CD. Is there a CD in the drive? Disconnect that too.

The noise is definitely coming from the CPU cooling fan, not the fan in the power supply. CD drives are empty, disconnected CD drives and same thing happens with the fan.

I replaced SATA cable with brand new SATA cable and got the same problem with the cooling fan running high speed and noisy. Unplugged the cooling fan and powered on PC and it turned off in about five seconds, approximately same amount of time the fan would run at high speed before shutting off computer.

Is the motherboard sensing something is overheated? Any other suggestions?

The mother board could be sensing something. Can you put a drop of oil on the shaft of the fan? It has to spin freely.

I've oiled the fan shaft and it spins very easily and freely, but just as it was before. Still get the same problem though when turning on the computer.

I would probably throw in the towel & say the mother board is bad. If you want to flash the BIOS as a last chance, go for it.

thanks for all the help, I'll see if flashing the bios helps, guess it can't get any worse than it is now.