When removing the heatsink, the CPU was attached to the heatsink and came out. Several pins have been bent and I've straightened them out with a pocket knife but when I put it back in and turn on the computer, nothing comes up. The computer starts like normal but nothing comes up on the monitor at all. Is the CPU bad or should I try to straighten out the pins a little better? What happens if you don't put a CPU in and try to start it?