[SOLVED] SOLVED!!! Why is my 3070 ti only using x8 PCIe lanes?

Sep 28, 2021
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I noticed on GPU-Z and in BIOS that my GPU was set at x16 4.0 but running only at x8 4.0. I tried to stress test the GPU with kombuster and GPU-Z but no change. I removed all other expansion cards and only have my M.2 boot drive in. I have all high performance modes on and have checked the PCIE power state in windows which is off. Lastly, I reset all BIOs setting and still its only running at x8 4.0. Nothing on the mobo manual or 3070 ti manual explains why this would be happening.

I get the card will work fine with just x8 lanes but I want to understand why it's not using all x16 lanes.

System specs
- Strix 3070 ti
-Dark Hero mobo - https://dlcdnets.asus.com/pub/ASUS/...53_ROG_CROSSHAIR_VIII_DARK_HERO_UM_V2_WEB.pdf
-1tb M.2 SSD (in slot 2) have also tried it just in slot 1
-Ryzen 7 3700x
-TX-750M Gold PSU

Any insight would be appreciated. - Maybe I am missing a setting in BIOs?

UPDATE: if I add another expansion card in the second slot instead of delivering x8/x8 it delivers x4/x4… I’m pulling my hair out here :(

SOLUTION: NO WAY was this the solve.... I literally just took out my GPU for the THIRD TIME but this time I blew out the PCIe on the mother board and lightly cleaned the gold connectors with Isopropyl. BAM running at x16 gen 4.

Thanks.
 
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InvalidError

Titan
Moderator
I know that PCIe will scale transfer rate based on load, not sure about bus width. If you have your PCIe power plan set to 'balanced', it is possible that the PCIe bus load never gets high enough long enough to turn the full 4.0x16 on.

You could set the PCIe link state power management to disabled or the power plan to maximum performance and see if that changes anything.
 
Sep 28, 2021
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I know that PCIe will scale transfer rate based on load, not sure about bus width. If you have your PCIe power plan set to 'balanced', it is possible that the PCIe bus load never gets high enough long enough to turn the full 4.0x16 on.

You could set the PCIe link state power management to disabled or the power plan to maximum performance and see if that changes anything.
Thanks, this is what I had thought too, but confirmed I have my power mode set to ultimate, and power state is disabled as well. No changes.
 
Sep 28, 2021
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Are you using riser cable? Have seen no display issues forcing pcie3 in bios to work with riser cable but limiting lanes is a first for me, and is another apparent issue.

Mention of it here,

View: https://www.reddit.com/r/ASUS/comments/kiygl1/question_for_owners_of_viii_hero_and_dark_hero/
I will take a look at this thread. I am not using a riser. I did try and force the card to use pcie gen 3 hoping it was just a scaling issue. But it just displayed x8 gen 3. In both gpuz and in bios.
 
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Sep 28, 2021
6
0
10
NO WAY was this the solve.... I literally just took out my GPU for the THIRD TIME but this time I blew out the PCIe on the mother board and lightly cleaned the gold connectors with Isopropyl. BAM running at x16 gen 4.