I installed a new CPU onto the motherboard, turned the power supply on and the following happenned (when the computer was OFF): 1) There was some smoke going from the inside of power supply. 2) All fans were on (although the computer was off) 3) RAM LEDs were blinking (instead being off) 4) Power LED on MBO was off (instead on) Later I found out that I accidentally misoriented 4-pin CPU power connector (I rotated it 90 degrees counterclockwise from the intended orientation). When I repeat the same procedure with properly oriented CPU power connector all symptoms above are the same except there is no smoke. I tested if power supply is ok by bridging black and green wires from 24-pin connector and it works fine. It seems the motherbord is fried? What else could have been fried? What is the probability that CPU is fried also?
Chances of the cpu being fried are slim, but it's a possibility. I would think it's the motherboard if the power supply tests fine.