mac pro will not turn on or wake from sleep mode

Hi everyone,

My mac pro 5,1 will not wake up from sleep mode. The power light will turn on completely but the fan will not rotate. no signal nothing. Second problem. I will power on the mac and nothing turns on. It makes a clickin noise but no light on the power button. Then i press button again it makes another clicking noise. The third time i press the button it will turn on. It just started doing all of these. I have taken it to a mac repair shop that recommended by apple and still they could not find the problem. Any advice on this problem.