If I plug a power supply to only the motherboard will that tell me if the motherboard is dead or not?

I have an old computer that got burnt out in a lightning storm..and for the past year I thought the whole thing was dead..But I got bored tonight and found that the video card and the DVD writer worked in another computer of mine..

I know for sure that the lightning killed my HDD and my power supply.. If I take an old power supply and plug it in the the motherboard will that tell me if its dead or not? Also the computer that shorted was a small form factor PC and uses a 125v power supply and I only have a larger power supply to test…