Computer Wont Power Up With 4 pin connected

[NoobsRus2015]

So it started off when i got my new rig it came on fine but no picture to the monitor, i had saw i had forgot to plug the 4-pin into the mobo (Asrock Fm2a75 Pro4-M) when i plugged it in the computer doesn't come on at all nothing happens but when i take it out the board comes on just fine ive tried taking out the graphics etc, nothing work... my powersupply has 4+4 pin and the board has 8 pin is that the problem... it started smoking once.

 

[popatim]

Time to breadboard the build and see if something was shorting on the case.
Basically take the motherbd out with cpu & 1 ram stick still on it and set it on a non-conductive static safe work area.
Take the power supply out and connect it to the motherbd correctly. Plug the PSU into the wall.
Connect a working monitor to the motherbd.

Short the pwrbtn# & gnd header pins briefly to turn it on
If it smokes unplug it immediately.

if it still doesnt work you can check the psu voltages, double check the installation of the ram and cpu or try a different ram slot.