Computer keeps rebooting.

You guys are probably getting tired of hearing from guys with computer problems, but I'd still like to ask you something because my computer keeps rebooting.

First i get this "CMOS checksum error, defaults loaded."
Then i get the choice or i can press F1 and continue, or i can press Del and enter BIOS.

When i press F1, however, my hard drive seems to be making a crackling noise for about half a second and then i get the choice to boot the system in safe mode. when i press Enter, no matter what i choose, the hard drive makes the same noise for about 2 seconds and then the computer reboots and the entire process begins all over again. Please help.

Thanks in advance.

What is your OS?

Can you get in Safe mode?

>>2
No matter what i do, before it should have booted windows at all my hard drive makes a crackling noise and it reboots.

Have you considered formatting? That would solve it. Just back up any important files using a linux live CD.

check s.m.a.r.t. status of your disk, i think your disk died