Question GPU only running at PCI-e 8x

[Deleted member 2855321]

GPU-Z says that my graphics card (RX 580 4GB) is only running at PCI-e 2.0 8x, but my motherboard should support 16x (it's even written on the board). CPU-Z also shows that the link width is 8x, but the max supported is 16x. There's only one PCI-e slot on my motherboard.

What can be causing this? I already went to the BIOS, but nothing mentioned PCI-e lanes or anything similar. I'm also using the Ultimate Performance power plan on Windows.

 

[kanewolf]

Are you checking this while heavily using the GPU? GPUs change the PCIe width to save power when lightly used.

 

[Dj0gany]

it can be you have a rlly old mobo that has a PCIe gen 2.0 slot ,which will make any pcie gen 3.0 x16 gpu run at 2x less bandwidth in your case that is x8.

 

[COLGeek]

Try this. Remove the GPU and then re-start the system using only the integrated GPU. After the system fully re-starts, power down and re-install the GPU. Make sure you firmly insert into the slot.

Fire back up and see if it is re-detected properly.

 

[cryoburner]

Are you checking this while heavily using the GPU? GPUs change the PCIe width to save power when lightly used.

To add to that a bit, you can hit the little question mark next to that box in GPU-Z, then hit the button to start a render test to put the card under load, and you may see the reported bus width change within a few seconds.

 

[Deleted member 2855321]

Are you checking this while heavily using the GPU? GPUs change the PCIe width to save power when lightly used.

Yes, I was using GPU-Z's Render Test while taking the screenshots.

 

[SkyNetRising]

Motherboard model name?
Are you using top PCIE x16 slot for your graphics card?

 

[Deleted member 2855321]

Try this. Remove the GPU and then re-start the system using only the integrated GPU. After the system fully re-starts, power down and re-install the GPU. Make sure you firmly insert into the slot.

Fire back up and see if it is re-detected properly.

I tried this but it's still at 8x 2.0.

 

[SkyNetRising]

Is it this one?
Intel® Desktop Board DB85FL

 

[Deleted member 2855321]

Is it this one?
Intel® Desktop Board DB85FL

No, it's this one: