Question Nvidia RTX 3090 Stuck at PCIe x16 4.0 @ x1 3.0

[Malzbier]

Hello together.
Sadly im currently stuck on this kind of issue that i cant seem to be able to resolve:

(Sorry in case this fits more in the Mainbord catigory)

My NVIDIA GeForce RTX 3090 Seems to be the bottleneck in a lot of games (witch it should not be)
Testing arround i saw that the Bus interface in GPU-Z (2.40.0) seems to be stuck at PCIe x16 4.0 @ x1 3.0
Yes i tested it with the incuded stress test , furmark , and different games. (happy to test different tools / benchmarks)
GPU driver updated , reinstalled , removed and reinstalled , no difference.
Windows energy saveing mode set to max power

My first instinct would be that i somhow messed up and overloaded my PCI-E lanes so the GPU does not get what it needs.
The main borad is a ROG MAXIMUS X HERO ( tested before frehs bios update)
(handbook for quick acess) https://dlcdnets.asus.com/pub/ASUS/..._HERO/E13645_ROG_MAXIMUS_X_HERO_UM_V2_WEB.pdf

(2) PCIEX16/X8_1 is my 3090

(5) PCIEX1_3 is a sata controller (PCI-E 2.0 2x lanes)

also Have one 960 EVO NVMe M.2 SSD (250 GB) (PCIe 3.0 x4, NVMe™ 1.2 )

PCIe_x16/x8_1 slot switches to x8 mode when PCIe_x8_2 slot is occupied
that im fine with since i dont use the the number 4 Slot



General component overview:
GPU : Asus NVIDIA GeForce RTX 3090
CPU: Intel core i7 8086k
Memory: 64GB DDR4 Ducal channel mode
Mainboard: Ausus ROG MAXIMUS X HERO
OS: Windows 10 build 19045.5073


Any hint regarding what i could test woulkd be very apriciated.

 

[Lutfij]

Welcome to the forums, newcomer!

I went look through your motherboard manual, PCIe_x16_1/x8_1 and PCIe_x8_2 are shared among eachother. While PCIe_x4_3 and PCIe_x1_3 both share bandwidth.

Ausus ROG MAXIMUS X HERO
What BIOS version are you on?

The main borad is a ROG MAXIMUS X HERO ( tested before frehs bios update)
Did you clear the CMOS after your stated BIOS update?

 

[Malzbier]

First of thanks for thaking the time to take a look.

Welcome to the forums, newcomer!

I went look through your motherboard manual, PCIe_x16_1/x8_1 and PCIe_x8_2 are shared among eachother. While PCIe_x4_3 and PCIe_x1_3 both share bandwidth.

Ausus ROG MAXIMUS X HERO
What BIOS version are you on?

The main borad is a ROG MAXIMUS X HERO ( tested before frehs bios update)
Did you clear the CMOS after your stated BIOS update?

Correct PCIe_x16_1/x8_1 and PCIe_x8_2 are shared but i dont use the second slot so no sharing should take place , even if it should not be 1x but 8x in the worth case.
Question is if the CPU z is maybe just not showing the correct value.

The thing is that the CPU only has 16 PCIE lanes questiuon is if the PCIe_x4_3 and PCIe_x1_3 and the M.2 slots are handeld by the chipset so not taking away from the CPU lanes

Biso revision is :2503
From 09/25/2020
updated via the bios internal update tool

according to the website there is a 2701 version avaibale on the website
not sure why the toll did not get that
gone try that via the bishsflashback tool

Did you clear the CMOS after your stated BIOS update?
not 100% sure i did but it did reset all bios settings in the process.

 

[boju]

How long have you had the 3090 for? Was it bought second hand?

Have you tried reseating the card? Even try the 8x slot to see if there's a contact issue. Inspect 3090 slot contacts carefully for grime, perhaps clean contacts with isopropyl and lint free swabs. Also check the 3090 is seating fully not obstructed by anything.

 

[Malzbier]

How long have you had the 3090 for? Was it bought second hand?

Have you tried reseating the card? Even try the 8x slot to see if there's a contact issue. Inspect 3090 slot contacts carefully for grime, perhaps clean contacts with isopropyl and lint free swabs. Also check the 3090 is seating fully not obstructed by anything.

Newly bought card , bought it 07.2021 so not second hand and it did work for a LONG time but this issue may be undiagones for a bit over a year so hard do pin down what caused it.

Gone try a reseat tomorrow (and the bios update once i find a trstutworthy usb drive)

 

[rene641]

Do you have a MB version with or without onboard WiFi? Version with onboard WiFi has an option in BIOS to enable bifurcation. With bifurcation enabled it would be possible to check if GPU shows x8 3.0

Edit: Or simply remove the GPU from the PCIEX16/x8_1 slot, insert it into the PCIEX8_2 slot and see what GPU-Z shows.

 

[Malzbier]

Thanks for your Reccomendations

Reseting + one CMOS reset seems to have resolved the issue
(did let it disassambled over night)

Now i get the expecte perfomace without any issue the the GPU-Z Display shows
PCIe x16 4.0 @ x16 3.0 (like it should the card only has PCIE 3 in a 4 slot)

Thanks for all how have taken the time to read my issue and extra for thouse who responded.
A very nice wellcome to this community.