Computer not turning on.

So I am a member of a company that refurbishes old computers and gives them to schools. We received a TON of spare parts as a donation and I have been making them into full fledged computers, but I have run into a problem with one. One computer simply will not power on. When the power supply is turned on, the confirmation light on the motherboard will glow green, but the power switch still won't work. The motherboard came with no manual so I am not certain on the exact orientation of the front panel connectors, but since it is an intel motherboard I think I know the orientation. I took this picture if it helps, and when I took it I took out all other front panel connectors. http://imgur.com/KEcjlRD . On a side note, every other front panel connector also does not work, but the computer does. So is this a problem with the motherboard (which is about 3 years old), or the case (which is about 5). I would normally think the case but since none of the other front panel connectors are working, it seems a little odd, especially since they are separate entities inside the front panel. Any help is wonderful.