Question *Resolved* PCIE x16 slot stuck at x1 3.0 mode while gaming

[thepriceisright]

Hello all!

Finished building a new system. I gave my GF my "old" i9 9900k and RTX 2080ti. After upgrading I didn't see any increase in performance, in some cases it seemed worse. It's also "hitchy" while playing even though it shows a normal constant FPS in fraps/game/evga toolset. After some investigating and ruling out throttling/heat I noticed my graphics card is running at 1x v1.1 while idle and 1x 3.0 while stressed... Here are my specs:

i9 10900k (no OC, Noctua heatsink)
Gigabyte z490 Aorus Elite F20a BIOS
EVGA RTX 3090 FTW3 plugged into the first x16 slot
850W Seasonic Focus GX-850
Samsung 860 Evo SATA plugged into SATA 0
Samsung 950 Pro M.2
Samsung 960 Pro M.2
Intel 905p SSD plugged into the second PCIE 16x slot
Sound Blaster Z plugged into the last PCIE 1x slot




I know Intel is lacking PCIE lanes but I was under the assumption that, worst case, my board would run at 8x on the main PCIE x16 slot. Otherwise a 1x/16x/4x/1x PCIE lane configuration seemed likely for the respective slots starting at the top. My Intel 905P AIC has similar performance results as before on my "old" system so it seems like that one is running at the expected width.

Any help would be appreciated. I'd really hate to have to buy another motherboard/CPU. Nothing against AMD, in fact if I have to buy something new I'd probably start there. I'm just hoping this is fixable is all.

 

[damian101]

Maybe you have a hair or something else blocking a contact in your PCIe slot...
Or a bent socket pin.
Or a defective motherboard.
Or a defective CPU (unlikely).

 

[sdifox]

Look at your manual, there should be a table explaining pcie lane allocation.

 

[Iron Woode]

check your BIOS settings to see if there is something odd there.

One guy said he solved this same issue by loading defaults in the BIOS and then rebooted.

but something else could also be wrong.

 

[thepriceisright]

Look at your manual, there should be a table explaining pcie lane allocation.

The manual only covered that, in certain configs, some of the SATA ports would be disabled. The second PCIE x16 slot is wired for 4x and the manual seems to indicate all PCIE slots will work at their wired width no matter the configuration.

check your BIOS settings to see if there is something odd there.

One guy said he solved this same issue by loading defaults in the BIOS and then rebooted.

but something else could also be wrong.

Maybe you have a hair or something else blocking a contact in your PCIe slot...
Or a bent socket pin.
Or a defective motherboard.
Or a defective CPU (unlikely).

BIOS was showing it running at x1 as well and there was nothing to force it into any other mode and I didn't see anything that would indicate any kind of control over it or something that might impact it.

Good news is now it's fixed! Not sure what fixed it exactly but here's the procedure I went through if it helps someone else:

I was incorrect about my BIOS version in my first post, I had hastily moved through the prompts on the windows based utility and since I selected that it download from the web, I assumed it grabbed the latest version. It did not, and was re-applying the F5 BIOS that shipped with the board. So I downloaded the latest and ran the update (F20a), which then effed the motherboard as apparently this release is only meant for 11th gen.

So I went through the BIOS recovery procedure, which only worked by removing everything from the motherboard, including CPU and GPU. When removing everything I noticed there was a 3pin fan extension cable that *might* have been between the PCIE lock tab and the GPU, but not sure as the card is stupid big and you can't actually see anything in the case. Once the BIOS was recovered to the F6c BIOS and set back to factory defaults, I reinstalled everything making sure it was all seated and locked. Prior to this I repeatedly pushed on the card and adjusted the "sag" allowed for this large card to double check it wasn't a connection issue but I couldn't see the lock tab to verify. This time I made sure I heard it click (honestly have no idea if it clicked the first time).

Now the system acts normal. Games aren't hitching, BIOS and utilities show it running at 16x. There isn't a change in performance over the 2080ti at 4k in Anno but at least it's working!

Thank you all!!