Short power with more than 2 servos

shorted source power with more than 2 servos. I connect the servos to the Arduino board. Servos and arduino are powered by an atx pc power.(Servos power are conect directly to de source power). when work only one all found well but when work more than one the source power is shorted. I put zener and capacitor in parallel at the input paraleo if any problem was a power surge.. I can't do nothin more

Can you provide a simple schematic, or at least specifics on exactly what pins are connected to what?