Diagnosing a problem.

[torin3]

Current setup is 4 cards, 3 1080 Tis and 1 plain 1080. 2 power supplies.

I used to have separate UPSs on the PSUs, but I've switched over to one UPS, and swapped which PSU was supplying the motherboard, as the connecter was heating up.

System seems a bit more stable now too.

I did have a 1080 Ti card that went back to EVGA about a year back and was replaced. I still couldn't get it to work in my system, but I figured it was probably my system, and not the card.

So, since the system was behaving better, I'd see if the card would work, so I swapped out the plain 1080 for the RMA replacement Ti card.

It worked for a day or so (mostly) then kept having problems with the system. So I put the plain 1080 back in, and system is stable.

I also have a computer in my garage running 2 1080 Ti cards with no issues.

So....Here is my plan.

Pull one of the 1080 Ti cards from the garage system and replace it with the potentially questionable card. Give it a week or so and verify if it works there or not. If it does, leave it there.

Use the card pulled from the garage system to replace the 1080 plain card in my main computer. See if it works there. If it does, just leave it alone. If it does not, swap out the PSU that was scorching the motherboard power connections with a new PSU and try again.

Both PSUs are Corsairs of the same model and are 1000W each. I'm confident that they aren't having a problem because they are undersized.

Does this seem like a reasonable troubleshooting path?

Thanks!

 

[HayesK]

Perhaps the motherboard does not supply enough power to the pcie slots for 4x 1080Ti. Is there an extra power connector on the board, other than the 24 pin and 8 pin?

Could try power limit on the 1080Ti cards. I run my 1080Ti with 200w power limits.

May only need to limit one 1080Ti to be same power as the 1080.

 

[caddi daddi]

The connector roasting is A sign that to much power is being drawn through it, the motherboard draws power from the psu, the psu does not push power to the motherboard, it could also be that you have A bad terminal in that connector causing heat, so A 24 pin cable change might be called for.

I found in my notes, from back in the FX 8150 days, I found that one rail was weak giving low voltage, causing high amp draw to the motherboard giving heat at the connector and making the thing unstable.

 

[torin3]

The connector roasting is A sign that to much power is being drawn through it, the motherboard draws power from the psu, the psu does not push power to the motherboard, it could also be that you have A bad terminal in that connector causing heat, so A 24 pin cable change might be called for.

I found in my notes, from back in the FX 8150 days, I found that one rail was weak giving low voltage, causing high amp draw to the motherboard giving heat at the connector and making the thing unstable.

Well it had the hot-spot when one PSU was supplying the motherboard power. When I swapped to the other PSU supplying the motherboard power, it didn't get hot anymore. So, apparently, the issue is related to that PSU. I don't know if the connecting pin was getting corroded or what, but it isn't happening from the other PSU connector.

 

[torin3]

Perhaps the motherboard does not supply enough power to the pcie slots for 4x 1080Ti. Is there an extra power connector on the board, other than the 24 pin and 8 pin?

Could try power limit on the 1080Ti cards. I run my 1080Ti with 200w power limits.

May only need to limit one 1080Ti to be same power as the 1080.

I've got an Asus Z170-WS motherboard. It looks like there is a 6pin EATX12V_1 plugin spot that I haven't connected. I'll try that first. I've got to check to see that I have a matching cable though.

 

[HayesK]

The specs show four power connectors. Good luck!
1 x 24-pin EATX 12 V Power connector
1 x 6-pin EATX 12 V_1 Power connector(s)
2 x 8-pin ATX Power connector

 

[torin3]

Finally got the final connection in and put the 4th 1080Ti in last night.

Failed slot this morning. Going to continue with my original plan later today when I get back home.

 

[torin3]

So far the card in question seems to be working fine in a machine with only 2 cards.

I'll try the card I pulled from that system in the 4GPU system.

I'm using an EVGA 90 degree power cord adapter with the questionable location on the 4GPU system, and I'm wondering if something might be wrong with that.

I've got it because I can't get both plugs into the top of the GPU, but when I'm using the 1080 FE, it only needs one, and the end of the cable reaches.

I'm going to get a couple of PCIE power extensions and try if it fails with the EVGA adapter.

 

[torin3]

Well, in the 2 card system it would run 1 or 2 WU then fail. I tried it about 5 times. Stock settings, fans on high, and a very cold garage the last couple of days.

Now to see if I can get it replaced under warranty. It was already a warranty return and never worked, but the original warranty is probably expired by now.

Edit: Just over a year left on the warranty. Started the RMA process