Question GPU started randomly using only 1 lane

[DingoDangoDongo]

Hello,

So I was wondering if anyone knows how to debug this issue. Currently I'm using a 4080 super and I noticed that something was wrong with my GPU so I took a look at GPU Z and I noticed that the bus interface only uses 1 lane instead of the full 16 lanes. I had to reseat the GPU every time this issue happens and it'll use the 16 lanes again. I thought this was a motherboard issue so I switched motherboards but it looks like it might be a GPU issue. my thinking is that I might have to RMA the GPU but I want to be sure first before I do that. Could it be the PSU?

 

[kanewolf]

Hello,

So I was wondering if anyone knows how to debug this issue. Currently I'm using a 4080 super and I noticed that something was wrong with my GPU so I took a look at GPU Z and I noticed that the bus interface only uses 1 lane instead of the full 16 lanes. I had to reseat the GPU every time this issue happens and it'll use the 16 lanes again. I thought this was a motherboard issue so I switched motherboards but it looks like it might be a GPU issue. my thinking is that I might have to RMA the GPU but I want to be sure first before I do that. Could it be the PSU?

Was this screen capture taken when the card was under load? For power savings, cards drop the PCIe width when not tasked.

 

[COLGeek]

Click on the little question mark and a render test option will put the GPU under load and will update that information.

 

[DingoDangoDongo]

Was this screen capture taken when the card was under load? For power savings, cards drop the PCIe width when not tasked.

Click on the little question mark and a render test option will put the GPU under load and will update that information.

So I have tried doing that and I have also tried running applications that use the GPU but it always seems to stay at 1 lane. I had to reseat the GPU last night and then it was using 16 lanes again.

 

[SkyNetRising]

I had to reseat the GPU last night and then it was using 16 lanes again.

That's a heavy card. Are you using any supports to prevent gpu sag?

 

[DingoDangoDongo]

That's a heavy card. Are you using any supports to prevent gpu sag?

Yes, I was using the one provided by the GPU first but am now using the one provided by the motherboard

 

[DingoDangoDongo]

Still having this issue and reseating it doesn't always change it back to 16 lanes. Anyone know a possible cause for this?

 

[Cellie]

Do you happen to have another computer or another CPU at hand to test?

Last time I had issues with PCIe lanes it was either the mobo or CPU. Unfortunately it was 10 years ago. I had to RMA both around the same time and can no longer recall who was at fault for what, just that one of them caused the GPU to randomly freeze when switching lanes.

 

[kanewolf]

Still having this issue and reseating it doesn't always change it back to 16 lanes. Anyone know a possible cause for this?

Have you tried laying your PC on its back so the weight of the card is not pulling on it ?

 

[DingoDangoDongo]

Do you happen to have another computer or another CPU at hand to test?

Last time I had issues with PCIe lanes it was either the mobo or CPU. Unfortunately it was 10 years ago. I had to RMA both around the same time and can no longer recall who was at fault for what, just that one of them caused the GPU to randomly freeze when switching lanes.

Unfortunately I actually don't. The original mobo that I was using was only 3 months old and I switched to a different one and it was still happening.

Have you tried laying your PC on its back so the weight of the card is not pulling on it ?

I have tried that originally but it was still happening. It is currently being supported by a bracket that came with the mobo.

UPDATE: If I go into the BIOS for 5 minutes then boot from there it looks like it switches to 16 lanes. Not sure why this would happen but would this be a PSU or BIOS issue?

 

[COLGeek]

Unfortunately I actually don't. The original mobo that I was using was only 3 months old and I switched to a different one and it was still happening.

I have tried that originally but it was still happening. It is currently being supported by a bracket that came with the mobo.

UPDATE: If I go into the BIOS for 5 minutes then boot from there it looks like it switches to 16 lanes. Not sure why this would happen but would this be a PSU or BIOS issue?

Is your motherboard BIOS fully up to date?

 

[DingoDangoDongo]

Is your motherboard BIOS fully up to date?

It's off by a few versions and from what I can see it's an update for: Update AGESA to ComboAM5

 

[COLGeek]

It's off by a few versions and from what I can see it's an update for: Update AGESA to ComboAM5

I would update to the latest version. What is the make/model of your motherboard?

 

[DingoDangoDongo]

I would update to the latest version. What is the make/model of your motherboard?

The motherboard that I am currently using is the x670e Steel Legend. I know 2 other people who are running the same mobo and gpu but they aren't having this issue.
Also as stated in a previous comment the weird thing that I've noticed is if I boot up my PC first and it's only using 1x lane, if I shut it down and go into the BIOS for like a minute and then reboot it'll switch back to the 16x lanes.

 

[rene641]

Hi DingoDangoDongo, did you solve the problem? I have the same, but found that if I turn on bifurcation x8x8 in the bios, GPU-Z shows 8 lanes 4.0...
I have Gigabyte Z690 UD DDR4 and RTX 4080 Super, both second hand.

 

[DingoDangoDongo]

Hi DingoDangoDongo, did you solve the problem? I have the same, but found that if I turn on bifurcation x8x8 in the bios, GPU-Z shows 8 lanes 4.0...
I have Gigabyte Z690 UD DDR4 and RTX 4080 Super, both second hand.

So I didn't find the actual problem but I did find that if I boot into bios for like 30s and then reboot into windows it will be in 16 lanes

 

[RodroX]

Some insane things to try:

- Go into the BIOS and change/play-aound with the quick boot options, and/or make sure the "show setup F2 message", or something like that, is set to at least 30 seconds. See if any of that makes a difference.
- Go into the BIOS and look for the PCIE mode option, see if its set to PCIE 4.0, if it is try to set it to Auto, and see if that makes a difference.
- Most drastical thing to try: Load "BIOS default settings", save and reboot. You may need to go back inside the BIOS later to enable XMP and/or set other options you may need (like PL1, PL2, etc., etc. etc.)

 

[rene641]

My problem with 1 lane instead of the full 16 lanes is solved. I removed the backplate and cleaned the pcie lanes including the capacitors with IPA, I also cleaned the PCIE bus. Then I measured all the PCIE lanes with a multimeter, they were fine.
I turned on the computer without the graphics card, let it run for a while, restarted it with the reset button and turned it off after a while. I installed the graphics card, turned on the computer, opened GPU-Z and voilà…

 

[RodroX]

My problem with 1 lane instead of the full 16 lanes is solved. I removed the backplate and cleaned the pcie lanes including the capacitors with IPA, I also cleaned the PCIE bus. Then I measured all the PCIE lanes with a multimeter, they were fine.
I turned on the computer without the graphics card, let it run for a while, restarted it with the reset button and turned it off after a while. I installed the graphics card, turned on the computer, opened GPU-Z and voilà…

Glad to hear. Never cease to amaze me how dirt/dust/hair/grease can destroy connection on this very advanced and delicated devices.

Is always a healthy idea to keep the room your PC si clean of all that crap. And is even better if your PC is located over the desk, and not on the floor.

 

[rene641]

My success didn't last long, the very next time I started the x1 4.0 appeared again...
I turned on bifurcation x8x8 in the bios again and will wait until something in the PC dies or I do an upgrade. RTX 4080 Super running on x8 4.0 is sufficient for my gaming. I bought the card as second hand for 745 USD, that doesn't seem like a completely bad price to me.

Edit: I probably found the problem, a cracked capacitor on the PCIE line. Now I have to find someone to replace the capacitor...