Power Supply Randomly stops outputting power?

[Rehmanpa]

I have a strange power supply issue that I am in some serious need of help to resolve. I've spent quite a bit of time researching it with no resolution. I have an Ethereum mining rig that uses two power supplies, a corsair AX 1200, and a Seasonic 1250 Gold PSU. I have it connected via a dual power supply adapter.

In order to get all 5 GPUs to show up in windows, I had to plug the seasonic power supply into the main 24 pin, and the corsair into the secondary 24 pin slot. This ran just fine. I had it running like this for several days until about 2 days ago things went haywire. The machine shut itself off, and several hours later I went to investigate. I tried swapping the seasonic to the secondary PSU adapter and the corsair to the primary, and this allowed the machine to actually post. The seasonic psu was drawing zero watts from my killowatt meter, and only the 3 GPUs which were plugged into the corsair PSU were showing up on the device manager. Eventually I took the Seasonic power supply out of the machine, plugged it into a different computer where it started up just fine, then I plugged it back into the machine and everything ran fine. This worked for about a day. Then today, the thing turned off again. I went out to investigate and just like before, the seasonic power supply was only drawing about 3.8watts of power. I am going to try plugging it back into my other machine tomorrow to see if it will fix it, but I really need a solution for this. I can't keep unplugging it and plugging it back into the other computer.

Does anybody have any ideas/solutions for my problem? I am thinking (however unlikely it is) that maybe it's the PSU adapter that's causing the issues? Because they were running fine for several days, and then this stuff started happening. I'm really in need of some help, hopefully one of you TPU members will know how to fix this.

Thanks

Also, I have the CPUs plugged into the corsair PSU, which is plugged into the secondary adapter, and 3 of my GPUs with it. The other 2 are plugged into the seasonic, and the only way for those 2 to get registered was by plugging it into my main 24pin adapter slot (not the secondary one).

 

[Bill_Bright]

Where do the two PSUs get their power? If different wall outlets, I would run a small grounding wire between the two supplies just to make sure they have a "common" ground. If running through UPS to different wall outlets, then strap the two UPS grounds together. I would also use an AC Outlet Tester to ensure your outlet is properly wired and grounded. If not in the US, you should be able to find a similar tester for your mains connector at your local home improvement store. If the tester reports a problem, you need to have a certified electrician fix it.

 

[verycharbroiled]

perhaps one of the psus internal protection is kicking in for some reason. usually the only way internal protection gets reset is to remove ac power to it via switch or unplugging the ac cord. give it some time to reset (several minutes maybe) and try to fire it up again.

as others have mentioned both psus need to be at the same ground potential, both at the ac outlet and between the ground pins of the psus themselves. or weird things can happen.

 

[Rehmanpa]

perhaps one of the psus internal protection is kicking in for some reason. usually the only way internal protection gets reset is to remove ac power to it via switch or unplugging the ac cord. give it some time to reset (several minutes maybe) and try to fire it up again.

as others have mentioned both psus need to be at the same ground potential, both at the ac outlet and between the ground pins of the psus themselves. or weird things can happen.

I've tried giving it time and it doesn't work. Only way i solved this previously was plugging it into another pc, letting it boot up, then putting this one back into my miner and it magically fixed it.

Where do the two PSUs get their power? If different wall outlets, I would run a small grounding wire between the two supplies just to make sure they have a "common" ground. If running through UPS to different wall outlets, then strap the two UPS grounds together. I would also use an AC Outlet Tester to ensure your outlet is properly wired and grounded. If not in the US, you should be able to find a similar tester for your mains connector at your local home improvement store. If the tester reports a problem, you need to have a certified electrician fix it.

I made (with my electrician friend) an outside outlet panel box which is connected to dual 20amp circuits in my circuit breakers. I have 2 heavy duty extension cords, one plugged into each out circuit, hooked up to the box I made. How would I run a grounding wire between the two? Also, how come when I plugged it into that other PC and it turned on, then plugged it into this one it seemed to work?

 

[Aquinus]

If different wall outlets, I would run a small grounding wire between the two supplies just to make sure they have a "common" ground.

If they're different circuits, couldn't that be a bad idea if they're isolated grounds? I feel like that's just asking for a ground loop.

 

[Rehmanpa]

If they're different circuits, couldn't that be a bad idea if they're isolated grounds? I feel like that's just asking for a ground loop.

It's been working just fine up until about 2 days ago. It had been running for weeks without an issue. I just got the seasonic psu and it had been working fine for I think the last week and then things went crazy. Should I take like a metal wire and electrical tape it from the psu to the case with the other one in it?

 

[Aquinus]

This is what concerns me:

I had to plug the seasonic power supply into the main 24 pin, and the corsair into the secondary 24 pin slot.

Servers with redundant power supplies usually use something to bridge the two PSUs together before providing that power to the motherboard. You might be killing your hardware by running it like this. I don't actively have a good suggestion other than not doing it that way.

 

[Rehmanpa]

This is what concerns me:

Servers with redundant power supplies usually use something to bridge the two PSUs together before providing that power to the motherboard. You might be killing your hardware by running it like this. I don't actively have a good suggestion other than not doing it that way.

I'm using an adapter like this: https://www.amazon.com/dp/B00DL3L2J6/?tag=tec06d-20

 

[Mr.Scott]

The obvious answer is RMA the Seasonic. It's not working correctly.
Every once and a while you get a lemon. It happens to every manufacturer.

 

[Aquinus]

The obvious answer is RMA the Seasonic. It's not working correctly.
Every once and a while you get a lemon. It happens to every manufacturer.

That's definitely the bottom line.

 

[Rehmanpa]

That's definitely the bottom line.

I can't do that because I bought it off Craigslist unless I can still file a warranty request for it. But the thing works normally in another computer.

 

[Mr.Scott]

Then the Seasonic doesn't like the adapter. It trips the protections.
You'll need a different PSU.

 

[jaggerwild]

Its gimped, what do you want us to tell you? Its OK use it? Then have at it, if it works in another then swap that PSU for it. Seems to me you had too much power with them both. The 1 doesn't want to work with the other, so don't do it.

 

[Rehmanpa]

Then the Seasonic doesn't like the adapter. It trips the protections.
You'll need a different PSU.

So should I try getting a different adapter? Because it had been working fine then it suddenly seemed to stop working.

Its gimped, what do you want us to tell you? Its OK use it? Then have at it, if it works in another then swap that PSU for it. Seems to me you had too much power with them both. The 1 doesn't want to work with the other, so don't do it.

Well if you're asking me what I want you to tell me my answer would be a solution. What do you mean I have too much power with both of them? I have them each running on a separate 20amp circuit which would allow for more than 2000watts each, and considering that they're a 1250 and 1200 watt psu respectively, this should be a non issue. It had been working fine and I was hoping someone had some ideas about why it might have stopped working. Someone mentioned a ground loop, how could I effectively deal with that?

 

[Mr.Scott]

The issue isn't with the adapter, it's with the Seasonic.
That's what you need to change out.

 

[Rehmanpa]

The issue isn't with the adapter, it's with the Seasonic.
That's what you need to change out.

I'm going to try plugging it back into a different pc and seeing if it will work then like it had previously.

 

[MrGenius]

All the adapter does it make it so the secondary PSU gets turned off and on in sync with the primary PSU. Other than that the 2 PSUs operate completely independently of each other. Meaning...yeah...the adapter is definitely not the problem.

Oh...and the ground loop hypothesis is also lacking any sense. They are on separated circuits...again...operating completely independent of each other as far as power input/output..

 

[Aquinus]

Oh...and the ground loop hypothesis is also lacking any sense. They are on separated circuits...again...operating completely independent of each other as far as power input/output..

Any time you connect two grounds together, you open the possibility of creating a ground loop because two grounds don't always have the same electric potential, even if they're a common ground. On paper, it's supposed to be 0v but, in reality two grounds might not have a 0v potential difference for a variety of reasons which become more apparent when they're isolated. The most basic reason would be current getting induced on it from being next to the hot wire or a device is putting power into ground when it shouldn't be. Either way, this shouldn't be an issue because the guy hasn't connected the two grounds together.

The issue isn't with the adapter, it's with the Seasonic.
That's what you need to change out.

If the PSUs are connected directly together, they might be causing problems. The adapter by itself shouldn't cause issues but, if more than one PSU is plugged into the motherboard aside from that adapter, bad things could happen.

Support for multiple power supply units is often found in server machines, but its purpose is to keep the server running if one of the units fails, not to increase the maximum total power output. Second PSUs can be used to distribute the load if a single unit cannot cope by itself and it is safe to do so as long as any rail is powered by at most one supply. E.g., you can use the second PSU to power the hard drives, but the hard drives must be disconnected from the first PSU.

Indeed there are good reasons for not using multiple power sources in parallel. PSUs are normally switching; they operate by frequently toggling between full-on and full-off. The output voltage is regulated by spending more or less time in the on-state. If load increases, the voltage drops and the feedback controller reacts accordingly.

When two units are installed in parallel, two controllers are hard at work to maintain a stable voltage, but they are unaware of one another. As a result, they may enter a hysteresis loop by consistently overshooting their target. Alternatively, one unit might try to lower the output voltage but fail, because his partner is pushing the output in the other direction.

With a few tweaks, these problems can be avoided. The second PSU can be hooked up to the controller of the first to ensure the output remain stable and diodes are required to avoid one unit from pushing current into the other when both aren't working equally hard. I highly recommend experimenting with this for the sake of learning about electronics (remember, smoke is bad). If you just want more juice for your computer, I suggest you keep both power supplies isolated, or even simpler, get a more powerful unit.

https://superuser.com/questions/681919/using-multiple-power-supplies-in-one-pc

 

[Rehmanpa]

I'm going to be taking some wires and trying to make sure everything is grounded together In case it's an issue like that. I don't understand though why it had been working and then it suddenly stopped, then worked for a day and stoped. Seems weird to me. It's not like the psu is even being pushed that hard, just 2 r9 290s. And for a 1250s that's hardly anything.

 

[Bill_Bright]

If they're different circuits, couldn't that be a bad idea if they're isolated grounds? I feel like that's just asking for a ground loop.

That is EXACTLY why you must have a "common" ground! You are asking for a ground loop if you have more than one isolated ground so that is all the more IMMEDIATE reason to tie the two grounds together.

And for the record, no facility should have two separate isolated grounds - ever. If such an event occurred, a difference in potential is highly likely and it could cause someone to, for example, have one hand on a metal bread toaster who then grabs with the other hand the cold water faucet or refrigerator handle and gets zapped! Not good. If they have a heart pacemaker, it could be deadly. Other symptoms could include induced hum or buzzing in audio circuits, "noise" in video circuits, "ripple" riding DC, or disruption/instability in other circuits - especially high-speed, low voltage data circuits.

Problems with EMI/RFI (electromagnetic or radio frequency interference) being emitted or insufficiently suppressed can happen without proper system/common grounds.

Even two isolated circuits in the same facility should have a common ground to prevent a difference of potential. If there is no difference of potential, there can be no current flow between them.

So the objective is to tie all the grounds together.

I don't understand though why it had been working and then it suddenly stopped, then worked for a day and stoped.

You are assuming everything was in perfect condition before. There could easily be a loose wire somewhere that is affected by vibrations from heavy footfalls, or even simple expansion/contraction of matter as the room heats up and cools down throughout the day.

This is why I said to test your outlets.

I have 2 heavy duty extension cords, one plugged into each out circuit, hooked up to the box I made. How would I run a grounding wire between the two?

The easiest way is to run a small wire attached to a case screw of one PSU to a case screw of the other PSU. Note there will be very little current so a small 22 AWG gauge "hook-up" wire will do just fine.

And FTR, running two different extension cords is definitely not ideal. No two lengths of wire have the exact same resistance. This is even more so when you have connectors at each end. When the resistance to earth ground is different you WILL have different ground potentials. So once again, all the more reason to make sure the two PSUs are connected to the same "common" ground.

 

[verycharbroiled]

take a multimeter and measure the voltage across the psu cases (connect to a screw on the cases for a good connection) while powered up see what comes up. hopefully 0.000v

when using dual psus i usually take a 18 gauge wire with lugs and screw it into each psu via the psu screw mounting holes. usually isnt needed but hey its easy and cheap.

and if the psus are are on different branch circuits there may be a ground loop.. depends on how good the house wiring is.

ground loops suck. i run into them a lot in live sound reinforcement as stuff gets plugged into different branch circuits. sometimes we wind up using ground lifts.

 

[Rehmanpa]

I took a wire, put two (I think they're called wire nuts) and screwed one into the first psu and the other end into the same spot on the other one (in the case psu mount screw hole). No success
Going to try hooking up to different pc soon

 

[DeathtoGnomes]

you might need this to combine different PSU's

http://phanteks.com/PH-PWCOB.html

 

[Rehmanpa]

Hey guys, thanks for all the good thoughts/ideas. I plugged both power supplies into the same circuit yesterday and it seemed to have fixed it. The thing crashed today, and I managed to fix it by plugging one of the two cpu 8pin adapters into each power supply. This has been working since earlier today, and I'll update it tomorrow if it's still working. I think this was the fix I've been looking for.

 

[Final_Fighter]

how many cards are you running? a 1200w psu should be able to run 4 r9 290 for mining. you probably dont need 2 psu to begin with. i use an 850w evga bq series psu with 2 rx570s, 2 rx460s and 1 rx480 and its been working for 3 months now. no issues. i would think that a single 1200w would be enough