Dead PSU or dead motherboard? I can't tell.

Yesterday I put a new aftermarket heatsink in my computer.

Now, as I go to boot it back up, here's what happens.

Case power button does not work.
Motherboard manual boot/power button does not work.
The power LED, showing the motherboard is recieving power does light up.
The power LED is right next to the manual boot button.
The case & video card fans do not spin or light up.
I did flash the bios.
There is no visible damage to any component.
There was no sparking, smoke, or anything of the sort.
Taking out the RAM/CPU does not result in a beep of any sort.
I do not recieve any beep error codes at all.

What's up? Which piece is dead?

Have you properly inserted the case power switch in the right direction at the right port(I often mess this up).gigatrainer

Sorry to say, i think your bios is dead. Clear signs. you flashed it and it doesnt turn on(controls power) no lights turn on(cant unless told to by bios) no sounds(motherboard wont make sounds unless the bios chip wakes it up and tells it to do a cmos and post boot test) So, unless you can get another bios chip, your motherboard may be fried. Im almost positibe it is this. did it work after you flashed your bios, or did it stop working after?joshott