Hello.
I ask for help and advice.
With great chagrin, I found out that the 1080Ti FTW3 video card is operating in mode PCI-E x8.

To check the performance of the system, I installed another video card for comparison. With her everything is ok.

Tell me, are there any solutions to the problem?
The video card worked fine, there were no problems with it before.
PC configuration:
• ASRock X299 Taichi XE (BIOS 1.60);
• Intel Core i9-7960X 4600 MHz/1.16 V (Mesh 3200 MHz/1.13 V);
• G.Skill Flare X F4-3200C14D-16GFX 4x8 GB@4000 MHz cl17-17-16-34 1T (VDRAM 1.42 V, VCCSA/VCCIO 1.15V);
• EVGA GeForce GTX 1080 Ti FTW3 GAMING;
• Custom watercool system;
• Intel Optane SSD 905P 480 GB (Windows 10 Pro);
• Corsair AX1200i;
• Thermaltake Level 20.

Once you check the Bios as sajin mentioned, make sure there is nothing obviously wrong with the gold fingers on the GPU.

Hopefully you get it figured out soon.

BCav monitored something below, and I am adding this in as well. You should be able to look at the PCI slot in the motherboard bios to see what it shows when you boot.

Users have had this issue before and most of them was able to fix the issue.

Sajin
Does this issue occur on both the vbios's the card comes with?

Yes, unfortunately, the switching of bios did not change the situation. Also, the BIOS update did not help. 

the_Scarlet_one
Once you check the Bios as sajin mentioned, make sure there is nothing obviously wrong with the gold fingers on the GPU... 

Soket CPU checked first. Everything is in order there. Contact petals are not damaged. The processor was not removed from the package before installing the video card, only the video card was replaced when the computer was upgraded.
In addition, as I said earlier, the previous 1070Ti video card is working in the correct mode x16. When this problem was discovered, we specially reconnected the 1070Ti  -  with it the mode of operation was correct x16.

the_Scarlet_one
...You should be able to look at the PCI slot in the motherboard bios to see what it shows when you boot...

bcavnaugh
What is it showing under the NVIDIA Control Panel - System information on the Bottom Left? 
Did you set the PCIe Slots in the Bios to X16 GEN3 or leave them at Auto?

What is interesting, in the "System Information" section in the settings of the NVIDIA driver shows: PCI-Express x16 Gen3
But at the same time, the GPU-3 and CPU-3 show at the same time x8
In the BIOS settings of the motherboard I tried as well as forcibly set the Gen3 mode, tried to leave it in the AUTO - no difference, in the end, anyway x8  

See if the card does the same thing in another rig.

chris12599
@abugaev
Did you ever resolve this? I have the same issue. I tested 4 video cards on my AsRock X470 Master SLI/ac Bios v1.90. I have pictures but the forum gives me an error when i post them.
 
EVGA Geforce GTX 1060 SuperClocked Gaming (06G-P4-6163-KR)
EVGA Geforce GTX 960 SuperClocked Gaming (04G-P4-1962-KR)
Nvidia Geforce GTX 680
 
And for good measure, a PCIe 2.0 card. Which it confirmed was PCIe 2.0
EVGA Geforce GTX 570 Classified (012-P3-1578-AR)
 
Thanks.

It can be a software issue, a BIOS setup issue or a Hardware combo limit. 

The PCIe Population Rules of your MB + CPU + what You installed = PCIe bus Speed that is available
 
You MB Manual will tell you the "limits" of your MB + CPU combo
 
Sometimes these are False software readings ---> GPU-Z & other. 

So, Always make sure you have the latest software. 

Then test you GPU with the GPU-Z tool "Green ?"  that is how you run the PCIe test in GPU-Z
 

chris12599
Windows 10 1809 Ent x64 (patches up to date), Nvidia drivers, GPU-Z and CPU-Z all current.
 
The next step is placing the 3 PCIe 3.0 cards in my friends computer. His Nvidia 1080 shows PCIe 3.0 x16 under system information in the Nvidia control panel.
 
My MBD and CPU are both PCIe 3.0 compliant......
ASRock X470 Master SLI/AC AM4 AMD Promontory
 
- 2 x PCI Express 3.0 x16 Slots
 
.....or so i thought.
 
AMD RYZEN 5 2400G Quad-Core 3.6 GHz (3.9 GHz Turbo) Socket AM4 65W YD2400C5FBBOX with Vega graphics
 
PCI Express Version: PCIe 3.0 x8

A little fact that NewEgg left out. Thanks for making me double check. I would need to upgrade to a Ryzen 5 2600X/2600 for x16.

Happy to Help
 
Sorry your hardware combo is limiting your desire to run 3.0 x16 on all cards
 
However the performance "loss" @ x8 on PCIe 3.0 is Very Small

Hello everyone, dear forum users.
Problems with 8x remained problems. I tried to rearrange the video card to another computer. The result has not changed - 8x. What is interesting when installing other video cards - the bus speed immediately becomes 16x.
I suppose that the true reason here is not in any drivers, or incorrect display, but there is one reason and this reason is obvious - a video card malfunction. I know for sure that a fully functional video card should not operate at a speed of 8x, even if the difference between 8x and 16x is small.
In the end, I plan to contact the PMA. After all, this is a warranty case?

bcavnaugh
 Slide down to the Bottom to see.

Ну вот до этого, в другом компьютере на скрине сдвинуто как Вы просите.

 

abugaev
In the end, I plan to contact the PMA. After all, this is a warranty case?

Yep.