Power doesnt turn on.. Motherboard problem? or PowerSupply problem?

Hi guys.
I dropped my desktop (not that hard) when it wasnt turned on,
and i saw a little spark from the inside of the desktop.
I tried to turn on my desktop, but the green power LED goes off, and
nothing happens. The fan doesnt start... nothing.
i tried disconnecting things one by one. RAMs, Harddrive,Graphic card, even the CD drive.
no changes were made. it was still the same.
However, when i disconnect the motherboard, the LED never went off but still fan doesnt start and nothing happens.
Whats the problem?

 

Hi,

First try plugging the power cord into a different, known good outlet. Also, try a different power cord as well to rule that out as well. Then I would try doing a minimal boot , with just the cpu, video card, and 1 stick of ram installed and with everything else disconnected. If that doesnt work, check the power button switch to see if it is broken. Also check where the power switch plugs into the motherboard to be sure that it hasnt come loose or come off its connector. If that all looks ok, I would then try swapping the power supply with a known good one and try the minimal boot again. If still no power, I would then look at swapping the system board.