[Archduke Tips]

Sounds like it is your BIOS.
Your BIOS is a programmable read only memory that controls the computer when you first turn it on. It is responsible for telling your motherboard to load the operating system from your hard disk.

You could try reprogramming the BIOS. This is usually done by putting in a floppy disk with the BIOS program on it and holding a certain set of keys while the computer starts. You will have to look more into your specific type of motherboard to figure out how it is done. This might fix your problem for awhile...

Unfortunately, from what you have told me it sounds like your computer has a more serious problem. A component on your motherboard may be at the end of its life. Sometimes when you startup it works, and other times it doesn't. I would suggest that you attempt to reprogram your BIOS and see if that fixes things. Keep in mind, if you mess up your BIOS, your computer will essentially be a heavy paperweight until you fix it.