Hi folks, I have a older Mac 3.1 that I still use, and it is no longer turning on. The power button Led comes on, the fans start up, and when video card is in, it to spins up and stays on fast, but no chime and no video. I have unplugged all usb and pulled the hdd's and graphics card, still nothing. I got a hold of tech manual and pressed the diagnostic button on start up and when its powered on and I see the Led 2 is on and Led 9 is on. Led 8 does not come on. I have tried with the ram sticks removed and with the ram boards themselves removed and still nothing. I have tried the original graphics card and a Nvidia GeForce card as well. I have tried the dvd 4 pin molex connector when powered up and get 5 v and 13 v on that plug. I have changed the Cr2032 Battery. I see 4 red led's light up on the ram boards when turned on initially. I am thinking the power supply due to LED 8 not coming on when the Diagnostic test button is pressed but... my research shows it could also be a bad mother board in some cases. Is there a way to test power supply, like a bench test? Is there a way to confirm if its the mother board? I have a 2012 Mac Pro but I didn't realize the power supplies are different. I have used compressed air to clean the inside of the board and fans and heat sinks. Please any help would be greatly appreciated.
Thanks
ps let me know if you need any more information
Thanks
ps let me know if you need any more information