Timer not operational?

Hey all. I want to first say that if this question has already been answered, I am sorry for asking it again. I looked but couldn't find it. That said, here I go. So I woke up this morning and turned on my computer and it didn't start up, but it gave 4 beeps rising in tone. I looked up the codes and I think that it means that my "timer is not operational." My question is: can that be fixed? If it can, how do I go about it? And if it IS fried, how could it have happened so I don't have this problem again. OK, I realize that is 3 questions but all the same... Thanks for any help you can give.

Mike

 

I'd spend three bucks on a new CMOS battery and see if that makes a difference.