As usual with broad questions there are many possible causes for this issue. Here is a short list of what I would check. If you are unsure about any of the terms or descriptions below DO NOT DO THIS YOURSELF, find a trained professional.
1. BIOS Settings
- If possible reboot the computer and press the correct key on your keyboard to access the BIOS, usually F2, F12 or even DEL. Once you are in the BIOS menu navigate to the RAID settings and ensure they are all turned off.
2. On-board battery
- Nearly every motherboard (after the companies stopped using the Dallas RT Chip) has an on-board battery. This battery ensures the BIOS does not lose any settings, but their voltage will eventually drop low enough that they no longer work.
3. Hard Drive
- It is possible that the hard drive has failed and the computer is unable to read it properly. This can result in the clicking sound described, which in my experience usually the result of the tiny read/write armature inside moving in ways it is not supposed to. Admittedly without actually being able to hear the sound being made this is all a guess.
There are other possibilities but these are the most likely causes, and can be found with any computer system.