Issue: GPU shows operating at x8 instead of x16 on PCIEX16_1. Validated only showing x8 while system under load (Battlefield 2042 and GPU-Z's load test) using NVIDIA Control Panel > Help > System information & GPU-Z.
MOBO: Asus B650E-E Gaming WiFi
CPU: AMD Ryzen 7 7800X3D
RAM: Trident Z5 Neo RGB 32GB DDR5 6000MHz CL30 AMD EXPO
GPU: EVGA GeForce RTX 3080 FTW3 Ultra Gaming 10GB Triple Fan PCI-E 4.0
* WD Black SN850X gen4 2TB
* Kingston KC3000 gen4 1TB
* WD Blue SN550 gen3 1TB
* Crucial 500GB
Per ASUS' bifurcation table, CPU supports 1x16 (GPU at x16) & 2x4 (M.2_1 and M.2_2). M.2_3 splits the x16 lane. M.2_4 and SATA are chipset lanes, not CPU.
Based on this, Physical configuration is as follows:
- GPU connected to PCIe x16_1
- M.2 [WD_Black] connected to M.2_1
- M.2 [Kingston] connected to M.2_2
- M.2_3 intentionally left empty
- M.2 [WD_Blue] connected to M.2_4
- SATA_1 SSD
BIOS versions tested:
1410 > current
- PCIe manually set to Gen 4 & PCIEX16
- M.2_1 and M.2_2 manually set to Gen 4
- Chipset Link mode set to Gen 4
Windows 11 OS settings:
- PCI Express > Link State Power Management: Off
BIOS 1409, cleared CMOS, reapplied BIOS settings mentioned above. Booted and tested per validation above.
Cleared CMOS, flashed to beta BIOS 1410. Reapplied BIOS settings mentioned above. Booted and tested per validation above.
>> 😓 Still persisting. Anyone see any glaring causes or fixes?
Will report back if I find any different findings. Welcoming other suggestions for fixing.
Steps still to take: Try with a different GPU, disconnect M.2_1, disconnect M.2_2, disconnect M.2_4, disconnect SATA.
Tested with another GPU that is known to operate at x16 in another build, it is also showing x8 when connected to this board.
Disconnected SATA and other M.2s, regardless of configuration, GPU still only showing x8.
Out of ideas now..
RMA my friend. My replacement B650E-E has been perfect.
The store I bought it from was able to exchange it for me, if you're in the return window give that a try. Easier than dealing with Asus support.
Have you attempted to run your pc with default bios settings to see if it's getting tripped up by some of the configurations made? Perhaps the auto mode for bifurcation is getting trip and needs to disable one of the other x16 lanes. Unfortunately I don't see a BIOS manual for your board (for what ever reason), but you can see how it's set up for the x670 series in the below screenshot. Hope this saves a trip back to the shops for a replacement.