im a computer tech from ky, have you tried resetting the bios on your board..
1.take BATTERY OUT
2.find bios switch
3. change it from 1to2 to 2to3
4.leave it there for a minute, then poweron the pc
5. then shutdown the pc, and reincert battery
6.try starting up the computer again
7. if nothing again make sure all power/ground wires are connected properly
8. if still nothing its 2 things, processor or board! 90% of the time, its a processor!
what kind of board are you using?