Just, as far as I know if your motherboard was bricked then it wouldn't start at all...
Not exactly. If just some devices/parts burned (for example graphic port)...
I've got the same problem with my old computer.
But let's play Dr. House game :
* PC restarts after 20 sec. ( excludes : Graphic card [But I'm not 100% sure ;/])
* Monitor on stand-by mode. (excludes : Monitor [checked], AC [checked])
Anyway, I'm about to buy AC, Motherboard and processor, so 99%, that I'll repair that ;p