Mb won't boot, is my psu bad?

I will point out a few things first however, the gray wire i tested 3 times when "on", at start/halfway thought testing other pins/at end of pin testing. Each time i got a slightly but clearly different result. In otherwords this pin was very very slowly increasing in voltage. From the lowest reading 104mv to the highest 107mv was the span of at least 10 minutes while i was testing other pins.

Secondly, pins 10/11 gave me negative numbers when "off" which seemed a bit odd. On pin 11 off i forgot to put a - sign.

Thirdly, pins 10/11 were flucuating fast, which is why i put -154 to -157 mv. it would go back and forth between 154 155 156 157 then back down to 154, all within 5-10 seconds.

lastly, these readings were taken while connected to the motherboard, not sure if that matters or not?

Anyways i have the readings, now i just need someone skilled in this area to diagnose this. This is for a motherboard that will not boot up/ no bios screen.

p.s. sorry about the hand writting i was using my left hand while testing with my other

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  1. the mb voltage look fine. most new mb if you look where you got the photo dont use the gray cable. most new mb wont power on if there a dead short. i would start with the simple stuff did you use the brass case standoffs or did you screw the mb into the mb tray and short it out. also check the rear i\o shield some of them have long fingers that can short out mb. same for after market heat sinks with metal back plates. on the mb check that the cpu jumper is right and that the 4/8 pin pci power cable is connected. make sure you used the 8 pin cable that bade up of two 4 pin connectors. some time people use the pci power cables (6 plus 2 pin cables) for that port and they wont work. on the mb check that the case cables are on right. if the case has a daughter board check that the cables are on tight.
  2. if mb's dont use the grey wire how does it know to turn on......
  3. 5v green wire is now use as an electronic switch.
  4. id like to see a link/quote to that info, because i have a computer thats 4 years newer than the one in question and its grey wire is showing 3v+ on its grey line when on indicating something is clearly wrong with the old one and most likely the reason its not turning on...
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