Hey, everyone. I got a problem that my mac pro 2009 doesn't start up. Yesterday, I use it but it shutdown suddenly. Then I press the start button again and it boot about 15 sec then shutdown. After this, I can't start up anymore when I press the start button. I try to check anything following this http://tim.id.au/laptops/apple/macpro/ma... When I plug the power cord, the OVTMP CPUA and OVTMP CPUB LEDs flash red. Press the DIAG button, the 5V STBY LED illuminates Disconnect the front panel board and momentarily jump the SYS_PWR, no any response. Reduce computer to minimal configuration, 5V STBY LED illuminates. But I still don't know which part broken. Can anyone help me or tell me which part I can check? Whether the OVTMP CPU A, B LEDs, and 5V STBY LED illuminating means the power supply and backplane board is ok? Thanks a lot.