Fried CPU or motherboard?

[aaron_29045]

I recently tried to fix my brother in laws operating system with my computer by hot plugging his hdd drive into my computer. When I did this, it didn't read it, but sparked really bad when I plugged it in. I restart the system and the hdd started sparking like crazy. I unplugged it immediately and the whole system shut down and smelled something burnt, which I think was the hdd because I didn't smell anything IN the case. Now it wont post. I don't see any burnt capacitors, and tried another PSU. Same problem. The lights on the motherboard come on and the fans spin, but immediately shut down after.
What have I fried?!

 

[jay32267]

My best guess is the motherboard took the hit. PSUs tend to be able to handle a short pretty well. I would think the components in the SATA data circuit on the MB are more susceptible to damage.