Dead CPU or MoBo?

[mikemassi]

Hi everyone. Yesterday, after a thunderstorm, I was browsing in my PC, then it shutted down, I tried to turn it on again but nothing happened, no beep, no power led, no fans spinning, I unplugged the power cord of the PSU, tried again, and the PC went on, no POST beep, but the PSU and MoBo plugged fans were spinning and the power led was on, I also detected HDD activity, so I unplugged the power cord and tried again, this time it didn't turn on like the first time, so I opened the case and cleared CMOS, removed GPU, RAM modules and unplugged HDDs, nothing happened, then I replaced CMOS battery and it turned on but again, no POST beep, fans spinning and power led on, then, I removed CPU, and it didn't make any difference , PC turns on but no POST, I tried another PSU, and same results, I replaced CPU again without heathsink and it feel warm after short time, I just can't realize if I need to replace MoBo or CPU, help me please. Thanks.

PC specs:

CPU: AMD Fx 6300 @ 4.4 GHz
MoBo: Gigabyte GA-78LMT-S2PT
PSU: EVGA 500 watts bronze
HS: Cooler Master 212 evo + AS5
GPU: Zotac GTX 960
RAM: 2x Kingston 8 GB 1333

 

[gingerrankin]

Never connect the PC without the CPU cooler. A few seconds are enough to fry the CPU.

 

[RBuczynski]

^You are right. However, to fry fx6300 he will need to give outer layer temperature circa 100C, which is not possible to get within a few seconds (IMO). I've tried similar trick with i5 on 1150 and it started to getting warm after ~30 sec up to 1 minute. Even without thermal paste and just with cooper and alu heatsink after few minutes in uefi it get to circa 55. Few seconds (but only a few, not many more) should be rather fine.

Best option to check if it's motherboard or cpu (maybe both?) will be finding new/used but working motherboard with this socket (AM3+ is it?) and testing it quickly. Be aware that motherboard might have power sections damaged - that could result in damaging good cpu. If you have warranty for motherboard, use it. Or try to find (after getting to know which part is dead) pc-service which can repair it. It's a shame to throw away broken stuff without even trying to repair it (if you dare).

 

[mikemassi]

Was the mobo, I found a little clue, when CPU was connected, yGPU fans keep on, when CPU unmounted, GPU fans kick on and then turn off, I figure that a dead cpu could give the same result as removed, also the CPU get warm, so I tried replacing MoBo and worked