Slot 3 won't run on x16

[Fabulist]

Hello everyone,

I moved my single GPU (and only PCI card) to Slot 3 for airflow purposes, and for some reason the lane insists on running on x8 instead of x16. Disabling the other 3 lanes from the switches makes no difference, nor does removing the batter.

Does anyone know why?

Thank you in advance.

[Fabulist]

Bump, is it not supposed to?

[Onimax]

Hi Fabulist,

which slot are you exactly reffering to and also what CPU do you have?

Taken from the RV10 manual (should be the same for the RVE):

Slot No. Slot Description
1 PCIe 3.0 x16/x8_1 slot
2 PCIe 3.0 x8_2 slot
3 PCIe 3.0 x4_1 slot
4 PCIe 3.0 x16/8_3 slot
5 PCIe 3.0 x1_1 slot
6 PCIe 3.0 x8_4 slot

Please check your manual so that we are talking about the same slot. 🙂

Given that slot #3 is only working at x1 which I assume you are not talking about,
it may either bei slot #2 or slot #4 you meant.

Slot #2 is indeed only working at x8 and slot #4 ,depending on your CPU, works at either x8 or x16.

[Fabulist]

Sorry for this, I meant slot 4 or the 3rd from the slots that are x8 and up. The CPU is a 5960x so according to this the slot should support x16 even with two GPUs, but it should work on x16 with only one GPU as well right?

[Chino]

Fabulist wrote:
Sorry for this, I meant slot 4 or the 3rd from the slots that are x8 and up. The CPU is a 5960x so according to this the slot should support x16 even with two GPUs, but it should work on x16 with only one GPU as well right?

Which motherboard are you using?

[Onimax]

Chino wrote:
Which motherboard are you using?

Thi,s and also check if you are on the latest BIOS/UEFI.

It _should_ work, but on some BIOS/UEFI versions it seems to not do this - it's not the recommended configration though.

[Chino]

What CPU and motherboard do you have?

[Fabulist]

I am using the R5E and the latest BIOS. Is there anything else I can try before I start flashing other BIOS versions?

[Chino]

Fabulist wrote:
I am using the R5E and the latest BIOS. Is there anything else I can try before I start flashing other BIOS versions?

In that case, yes. The fourth slot on the R5E is a x16 slot. If you're using GPU-Z to check the speed, try running the render test.

[Fabulist]

Onimax wrote:
You could try clearing your CMOS and/or revert your machine to stock settings - overclocks can affect this.

I already did did that but nothing.

Chino wrote:
In that case, yes. The fourth slot on the R5E is a x16 slot. If you're using GPU-Z to check the speed, try running the render test.

Well I checked from within the BIOS, it is reported as x8 instead of x16, whiel Slot 1 is reported as x16.