|Did you just change any thing recently like the RAM. I have had this before when running error correcting RAM in a computer that does not support it.|
If you have not then pull the RAM out and put it back in. If still get the same BEEP then pull the RAM out all to gether and turn it on and you should get a BEEP that goes on and off. If not then most likely it is the CPU. I never recommend any one messing with that unless they know what they are doing but double check that the Cooling FAN is spinning up.