I just received a3080 Ti XC3 ULTRA HYDRO COPPER yesterday that seems to be stuck at 8x instead of operating at 16x. I replaced two 1080 Ti's in SLI, and they were running 16x and 8x, respectively because I was running a NU Audio card in slot 6 that would not allow the second GPU to use x16.  The NU is now in the x4 slot 5 that is usually covered by the second SLI card and a plastic cover on the X299 DARK. 

- Updated BIOS to 1.29
- Updated GPU firmware with X1 (per software recommendation)
- Removed audio card from PCIE slot
- Reset CMOS
- Set everything to defaults, including any overclocks and memory profile

PC Specs:

• EVGA X299 DARK
• Core i7 9800X @5Ghz OC
• EVGA RTX 3080 Ti XC3 Ultra HC
• Corsair Dominator Platinum 64GB @3600Mhz
•  EVGA NU Audio Card
• WD Black NVME 500GB
• Samsung 980 Pro 2TB

Cooling loop is mostly Aquacomputer gear with 2x D5 NEXT pumps and various sensors controlled by and Aquaero 5 Pro.

Thanks all...

I seemed to have done enough in terms of getting the performance where it should be. At least for the most part.  It seems that some of it has to do with running RTX features over top of traditional settings in game.  I tried letting GF Experience handle a few optimizations and it gave me a clue on Control (game) for example where it disabled certain features "due to DLSS being enabled" or "due to Ray Tracing". So that's helpful, but even with Destiny 2, where I was most surprised to see a problem last night, it's running like a champ around the 80-120 avg fps.  So mostly happy there... but more work to do here, I'm sure.

As for the x8 issue... that is where I need to spend time.  So here are the answers to your questions.

- Yes, it asked me to upgrade the firmware as soon as I ran X1
- I have 2x M.2 Drives on the MB, but I my 1080 Ti in the first slot ran @ x16 with another one in slot 4 @ x8 just prior to yanking them out yesterday.
- Removed iCue, I set the ram to hold the profile I like on the hardware.  Then uninstalled the app.  :)
- Hardline indeed.  It's really easy to see that it's seated solid.  I was a builder so I'm still pretty on-it about checking connectors for dust and seating everything nice and snug and clicky.  (but I did check the alignment last night... to be sure)

I'll answer this much and try the Cold Boot action now and report back...  I'm starting to wonder if it's a MB thing at this stage.

GPU-Z shows PCIe x16 @x8 3.0 (this is how I have been monitoring it).

Oh! And I am running two m.2’s as well.

P.S. it could be the motherboard as well, so this may take time to figure out, but hopefully we can help you figure it out quick.

My next suggestion would be to start by trying all of the bios switches. I doubt they will make a difference, but it’s easier than pulling the CPU just to verify the bios isn’t doing something wonky. Also, full bios reset is never a bad start.

After that, go into bios, advanced, configuration, PCIe Configuration, and verify everything is set to Gen 3 for the PCIe 1 and 4 (even if 4 doesn’t have a card for now).

After that, i would pull the CPU when you have a moment, and verify all of the socket pins are in good order. If the issue has happened in the past with any configuration, start at the brains of the board and work out from there. I know draining the loop is a chore, but it’s better to verify everything so that you know where the problem could be, and then work from there.

Tried the bios switches, and there is no BIOS on 2 and 3.  I even turned off the PCIe slots that are not being used with the dip switches.  I mean, the 1080 Ti worked fine in that slot.  I just don't get it...

Last night I restored defaults as well. 

bill1024
Call EVGA and tell them what you have tried and see if it is RMA time

 
Yup... thanks.  Already have a ticket.  

Took some time to reseat the GPU and re-configure the loop as well since I had it just working for cooling.  LOOKS GREAT!!  

Still operating @ x8

So I picked up a 3080 Ti FE at a local Best Buy and it’s still the same problem with the x8 in that slot.  I’ve removed everything but the boot NVME in the main slot. I’m going to do a full tear down and test everything on a test bench so I can actually get to an answer.

b3l13v3r
So I picked up a 3080 Ti FE at a local Best Buy and it’s still the same problem with the x8 in that slot.  I’ve removed everything but the boot NVME in the main slot. I’m going to do a full tear down and test everything on a test bench so I can actually get to an answer.

It's odd that two 3000 series GPU's run at x8 and your 1080's run fine at x16. Might be worth while to check all the pins and reseat the CPU as well. That's where, for those slots, the lanes originate from.

Soooo.  It turns out that the MB was getting flakey.  After putting it on the test bench with a different 1000w PSU, it was getting power as the lights were on, but no power up with the power button.  RMA it is... thanks to all of your suggestions.  Really appreciate everything!!

Moving the platform to Z690 KP and a 12900K.  I hoping that will solve some of the problems I having in terms of FPS in games.  My buddy has a 3080 with a 12700K and he's getting 30% better FPS than my 3080 Ti on a 9800x (120 fps avg on Destiny 2's tower area, vs. my 80 fps avg while standing next to his character in the same area).  We have similar RAM as he is on the DDR4 3200 version of Z690 while I'll be on DDR5 6200. But that 12700K must be doing something for him.

Open to any info you guys have on that.

I did… I took close up pics for EVGA as well.