Help me understand something, gtx1080+ax1200i

[Ardacer]

So recently I had a ton of problems with my gtx 1080, the screen would go black and fans ramp up, the OS would continue to work under it. In games, or in idle, sometimes it wouldn't even boot into windows.

 

Reliability history always said it's a driver problem.

 

On linux, the crashes were a lot rarer, and windows safe mode crashed only once. This first started happening couple months ago, but in the last month it was so often that it made the PC unusable.

 

Without the graphics card, system was stable.

 

Ram was good.

 

So there were only a couple of options.

 

1) Driver issues

 

I tried everything, from clean OS installs, ddu + a shit ton of older drivers, leaving only windows drivers, etc- it was sorta stable on the basic driver but even that would occasionally crash.

 

2) GTX 1080 was broken - I RMA'd the card. They stress tested it for 2 days, nothing.

 

3) Dust - I kept it as clean as it came from the box. 0 dust.

 

4) PSU - It's basically a new ax1200i PSU which I bought couple of years ago but never used until now. I mean, it could be it, but srsly..

 

5) Cables - the connection indicators for gtx 1080 cables were always white- meaning connected and powered. I connected the card and the PSU with 2 cables, one for the 6 pin, and one for 8 pin.

 

I didn't change anything. This setup was stable until some windows updates, or so I thought. But it happens in other OS'es too, so ..

 

What ended up fixing it, was connecting the PSU and GTX with only one cable. Why? I though, maybe the PSU has more than one voltage rails and it causes instabilities.

 

Nope, 1 rail.

 

How I noticed it: If you connect the 1080 (asus strix 08C) in the PCI slot only, indicators (2 of them) are red. Originally I thought if you connect voltage to them, they go white, but no! Just if you connect the cable to them, they go white.

 

But! If you connect, for example, the fractal edison modular cable to the card only, to the 8 pin only, it's white. To the 6 pin only, it's white. If you do the same with corsair's cables, 8 pin only, white. 6 pin only, RED! FAULTY CABLE!!!!! or not.. both the corsair cables that I had did it. If you  connect 2 corsait cables to gtx only, no psu, 8 pin is white, 6 pin is red, edison cables, both connectors white. If you connect only 1 corsair cable to both 8 and 6 pins, both white. All of this without power from PSU. If they are connected to PSU, both the 6 and 8 pins will go white anyway.

 

Also, the eddison and ax1200i psu have different modular cables, wires are connected differently, and psu side connectors are different.

 

What is going on.

 

Why does it work on one cable, and not on 2 cables? It makes no sense really. And It's not like the connectors are loose or anything like that, really.

 

 

[Computerjunk]

Graphics cards like the 1080 need more power than something like the 1050ti, that's why the 8-pin connector is on the card. So yes the card has to be connected to the motherboard via the PCI slot and also needs the 8-pin connection to supply enough power to have it run stable, if it still doesn't work then something might be wrong with the PSU

[Ardacer]

I gave it both the 8pin and 6 pin power, on 2 cables from ax1200i, and it was unstable. I gave it power from one cable to both connectors, and it's stable.

 

How. Why. Cables are fine. It makes no sense.

[Computerjunk]

1 minute ago, Ardacer said:

I gave it both the 8pin and 6 pin power, on 2 cables from ax1200i, and it was unstable. I gave it power from one cable to both connectors, and it's stable.

 

How. Why. Cables are fine. It makes no sense.

Having both of them connected could be overloading the card, I'm not entirely sure. The card could also be trying to switch which power source it's taking from which would  cause it to crash  when switching power sources. Personally I would connect only the 8-pin to PSU for power

[Ardacer]

Why would they bother placing both connectors there then. It doesn't add up.

[Computerjunk]

4 minutes ago, Ardacer said:

Why would they bother placing both connectors there then. It doesn't add up.

Probably for more compatibility with other psus

[DocSwag]

Are you plugging a 6 pin or 6+2 pin cable into the gpu?

[Ardacer]

both.

[DocSwag]

9 minutes ago, Ardacer said:

both.

So is the cable that is plugged into the GPUs 6 pin a 6+2 or just 6?

 

Also, please quote me in the future or I might not know you replied!

[Ardacer]

17 minutes ago, DocSwag said:

So is the cable that is plugged into the GPUs 6 pin a 6+2 or just 6?

 

Also, please quote me in the future or I might not know you replied!

Both. One cable has both 8 and 6 pins connectors. Its just that before, I used 2 such cables, one for 6, and one for 8. Now I use 1 cable for both 8 and 6. And it works.

[DocSwag]

3 hours ago, Ardacer said:

Both. One cable has both 8 and 6 pins connectors. Its just that before, I used 2 such cables, one for 6, and one for 8. Now I use 1 cable for both 8 and 6. And it works.

But was the cable that you used for 6 pin a 6+2 with you only using the 6 pin? Or just a 6 pin?

 

The reason I ask is because your psu has some 6 pin connections on it for plugging in peripherals, so it's possible that you connected the 6 pin connection on the gpu to one of those instead of a pcie power plug which could screw with things.

[Ardacer]

Both were connected to PCIe, always. The cables are:  modular connector for PCIe, and both 6+2 and 6 on the other side.

 

5 hours ago, DocSwag said:

 

[DocSwag]

14 minutes ago, Ardacer said:

Both were connected to PCIe, always. The cables are:  modular connector for PCIe, and both 6+2 and 6 on the other side.

 

So now that works for you?

 

The only thing I can think of is maybe the connector the 6 pin was connected to was broken or something. Seems really strange tbh

[0x1e]

53 minutes ago, Ardacer said:

Both were connected to PCIe, always. The cables are:  modular connector for PCIe, and both 6+2 and 6 on the other side.

 

I would say when you are only using one cable then the card down clocks because it has less power.

The lower clocks make the card stable, not the power output.

[Ardacer]

20 hours ago, DocSwag said:

So now that works for you?

 

The only thing I can think of is maybe the connector the 6 pin was connected to was broken or something. Seems really strange tbh

I thought that too. But what's really weird is that both cables in solo version work just fine. The ONLY explanation I can find is that corsair's inner cable wiring is weird and connecting it with 2 cables messes something up. No idea.

20 hours ago, 0x1e said:

I would say when you are only using one cable then the card down clocks because it has less power.

The lower clocks make the card stable, not the power output.

 

Doubt it. What would happen is that the cable would overheat (if it's not thick enough) as it's delivering more power now. To actually limit power to the gpu it'd need to have some resistance in it which, of course, it does, but it's negligible. Also said resistance might, depending on the cards input impedance, cause a voltage drop, making the card even more unstable