My CPU was struck by lightning and I am trying to figure out what's fried because when I power up the machine the green LED comes on and the orange (busy) light just sits there without flickering and the screen is blank. I took everything apart and tested it with my friend's PC. There is power going to the CD, DVD drives, the fan is getting its power from the motherboard. The hard drive is working and monitor is fine too. Does anyone know if I should replace the motherboard, and processor and would it be expensive to get it fixed? Or is there is anything else I can do to troubleshoot this problem? I have an HP Pavilion XL876 CPU. I'd appreciate any response. Thanks.

The motherboard from HP will have high replacment cost. How about the memory, did you check them too? Motherboard, memory and CPU (may be modem)replacments plus the headache when you find more to replace, you'd better go for a new system for less than $400 at Bestbuy. You should get house insurance to reimburse for the system. They do cover lightning damage, check it out. My recommendation is not necessary the best solution.