Asus z690 running only running X8 for Pci-e on rtx 3080

[wasakiqwe]

Hello Need help please as fast as you can.
First slot for GPU RUNNING AT X8. Asus z690 hero.

The problem started when I tried to change Pcie and M2-1 to gen 4. it was auto.

then I tried to put ssd to M2-2 but still something .

Bios update to last version, tried to disable power saving for pci.
Only p cores running on windows 10.

Cpu used intel 12900k

Storage firecuda 5301tb

Thanks

[Murph_9000]

There are a lot of different Z690 boards, which one do you have?

Some of the boards steal GPU PCIe lanes for M.2_1, forcing the GPU to run as x8. On those boards, the CPU's PCIe x4 storage lanes are on M.2_2. The board's user manual tells you if that's the case, if M.2_1 is included in the details about shared PCIe bandwidth. If that's the case, put your NVMe in M.2_2, leave M.2_1 empty, return the BIOS to "load optimised defaults", and see how it behaves (it could be that you've set something while trying to force PCIe slot behaviour that's now preventing it returning to x16 on the GPU slot).

Did you also update the Intel Management Engine (ME) when you updated the BIOS? You need to update both BIOS & ME, plus the ME driver, as a mismatch between BIOS & ME versions can cause issues.

[Nate152]

Hello Wasakiqwe

I have a similar setup.

With one ssd in the M2_1 slot, your ssd should run at x4 and your RTX 3080 should run at x16 as your 12900K has 20 pcie lanes.

Do you have any other pcie devices connected besides your ssd and gpu?

[wasakiqwe]

Model is ASUS Z690 Hero.
Only 1nvme connected on M2-2 now.

[1100R]

[Nate152]

Thank you for confirming.

In the bios, I have my ROG Strix 3090 ti set to Gen 4 and the ssd in the M.2_1 slot set to Gen 4.

Check in the bios you have your RTX 3080 set to Gen 4.

[JohnAb]

I have all NVME slots filled on my 690 Hero and my GPU still runs at 16x. Gen 4 drives in slots M.2_1 & M.2_2. The other slot, M.2_3 has a Gen 3 drive.

I didn't plan anything, it all just worked out fine. So I'm thinking it might be your BIOS settings. Mine are pretty much all on defaults, at least as far as PCIe settings are concerned.

[Sunfox]

None of the m.2 slots on the Hero will steal lanes. The only way to steal lanes is by installing something into the second PCIe slot.

If you have not done that, then you likely have a contact problem either with the GPU, the PCIe slot, or a bent pin in the CPU socket. Shouldn’t have to mess with BIOS settings for any of this.