PSU Clicking On then powering off & looping.

[TheDevastatedOne]

I have two higher end PSU's here.

One of them is an EVGA 1300 Supernova G2 when I jump the "power on" it begins to power up, fans spin, voltages go down the lines as I connected a case fan to the 12volt rail and it spins up as well. But then what sounds like a small faint relay clicks and it powers off, then powers back on again and repeats this power on/off loop.

I also have a new Raidmax 1000W Scorpio which does similar (right out of the retail box I might add) it will begin to power on then click & shut off. (This one does not attempt to restart until you un-jump the psu-on and then re-jump it.)

Notes:
When I first got the EVGA Supernova I decided like most PSU's before installing it, I would pre-test it with a jumper wire (paper clip test) just in case the PSU was faulty (so as to not damage my high end motherboard/GPU etc). However the first time I jumper booted the PSU there was a loud pop inside? I took it apart and looked around obsessively for hours under magnification and I cannot see anything wrong, no blown or bulging caps no blown IC's no broken solder joints nothing looks blackened etc.. it seems to make no sense if something popped that loud surely there should be something blown?
And yet the PSU still seems to output the normal 5v and 12v, the only issue is that it just does not stay on.

Any ideas where to focus/look would be a tremendous help!

[momaka]

Re: PSU Clicking On then powering off & looping.

These are high-power PSUs and likely need a minimum load on their output in order to work. A single fan (or two) or even some hard drives likely won't be enough. You need a bigger minimum load. If you have any 12v bulbs (car headlights and taillights or similar, or 12V halogen in the range of 20-50 Watts), use those and attach at least 40-50 Watts worth of load on the 12V rail (since this is a modern 12V -heavy PSU.) Then try jumpering PS-ON to ground to see if it works.

Extra note: if you used 50W halogen bulbs, don't go overboard with how many you put on the 12V rail. Halogen bulbs have a very low cold resistance and might trip the OCP protection on some PSUs. These being 1000+ Watt units, they might be OK... but letting you know just in case.

[TheDevastatedOne]

Re: PSU Clicking On then powering off & looping.

I am fairly certain the 1000w was installed in a motherboard and did the same thing.
But I will try plugging them into a lower end motherboard/cpu I have here to see what they do.

[TheDevastatedOne]

Re: PSU Clicking On then powering off & looping.

These are high-power PSUs and likely need a minimum load on their output in order to work. A single fan (or two) or even some hard drives likely won't be enough. You need a bigger minimum load. If you have any 12v bulbs (car headlights and taillights or similar, or 12V halogen in the range of 20-50 Watts), use those and attach at least 40-50 Watts worth of load on the 12V rail (since this is a modern 12V -heavy PSU.) Then try jumpering PS-ON to ground to see if it works...

Same thing when plugged into motherboard/cpu/ram/videocard.
Starts to power up, fans spin, video card fans spin, then powers off.

Interestingly one time I powered on the EVGA it began to go further into the boot process where you hear the PSU make a more "settled" sound like ok I'm going to post, it stayed on longer than other attempts, but then powered off.
-->It also seems the EVGA is dead now it won't power on at all (even with jumper wire across Power-on/Ground). Fuse is ok.