Blinking green light on Power Supply.

[RageIncoming]

I am working on a frends desktop that recently might have been hit by lightning. After a big storm their desktop would no longer power on. Now, I am no stranger to computers. I unplugged the motherboard main connector and I get a solid green light when I plug the psu in. Plug the main connector back in and plug the psu in I get blinking light again. So either its the PSU or mainboard. Im thinking psu since usually that is what goes first, but at the same time I am leaning towards mainboard. what do you all think?

On another note, Are these boards proprietary? I have a few standard ATX PSUs I could test my theory with but not if I have to rewire them.

[old_geekster]

@RageIncoming, welcome to the forum.

I agree with your diagnosis.  The PSU is most likely to be the culprit.  Here is a guide to help you troubleshoot it.

The PSU is a standard ATX.  You can use any brand that will fit.  Just measure the existing PSU and match it to the one you choose.  I like Corsair products because they provide clean, stable, power.  The motherboard are somewhat proprietary, but I have never had a member say that the one they chose wouldn't work.

Please click the Thumbs up + button if I have helped you and click Accept as Solution if your problem is solved.

[RageIncoming]

Well, I just tried a known working PSU and nothing happens. Are you sure this is not a proprietary psu pinout? I recently put together a HP z400 that had a different pinout. I have plugged in only the main power, cpu power, and front panel connectors. Does this computer have a chassis switch? I want to take a pin and jump the power on on the main connector to elimininate a bad power switch but if the pin out isnt the same it might short.

[old_geekster]

I just realized that you have Slimline model.  I must have typed an incorrect model when I did my research.  The PSU is definitely not a standard ATX.  Here is a PSU like the one in your computer.  As you will see, it does have a 24 pin ATX connector.  To my knowledge, they are not proprietary.

[RageIncoming]

I used a semi new 630w Rosewill Green 80+ PSU from one of my previous working builds that I upgraded. So far I hook everything up and hit the power and nothing happens. The psu does not turn on. So either the mainboard is dead,the switch is bad, or the pinout isn't std atx. I will start with the switch.

[RageIncoming]

I have a feeling it's the mainboard. Nothing happens when I use my PSU with it. I changed the switch and still nothing. I use a paperclip to ground the green and black main connector wire (PS ON > GRND) and the fans spin for 1 second then shutoff and repeat again unending. I am going to take the board out and bench test it just in case there is a weird ground fault in the case.

Update: Still no difference now. In fact, jumping PS ON doesnt even work now when connected to the mainboard.