Asus TUF B650-Plus WiFi M.2_1 slot issue

[hodjaev_ruslan]

Hey guys, I recently noticed that my recently built PC has an issue where my Samsung 990 Pro's speed is halved while being installed in the M.2_1 slot, which is a PCIe Gen 5. When using the software to check the transfer mode, it shows Gen 4.0 x 2 instead of Gen 4.0 x 4. The 980 Pro is using my M.2_2 slot (it also has the OS installed on it), which works at its max speed, and my older ADATA XPG Spectrix S40G is using the M.2_3 slot and works fine.

I have tried swapping the M.2_1 SSD with the M.2_3, and now the M.2_1 doesn't even show the XPG SSD installed in it, while the 990 Pro can now work in Gen 4.0 x 4 mode when using the M.2_3 slot. 

Is there something wrong I am doing? As far as I am concerned, the PCIe Gen 5 slot is backward compatible with older generations, but I don't get why the 990 Pro works in 4.0 x 2 mode and the ADATA XPG Spectrix S40G doesn't show up at all when being installed in the M.2_1 slot.

I even tried manually setting the link speed for each slot, and nothing has changed.

Do I need to change any settings in my BIOS? Maybe I am missing something. I would appreciate any help.

Just in case, my specs are:

MB: Asus TUF B650-Plus Wi-Fi

CPU: Ryzen 7 7800x3D

GPU: Asus TUF RTX4070 Ti Super

Storage: Samsung 990 Pro 1 Tb, Samsung 980 Pro 500Gb, and ADATA XPG Spectrix S40G 512Gb

[Silent_Scone]

Hi @hodjaev_ruslan 

Are you first able to confirm you're on the latest UEFI?

It may also be worthwhile checking the CPU mount and socket for any debris or bent pins. At Optimised Default, there's no configurative reason for the 990 not to be correctly detected.

[hodjaev_ruslan]

I have checked everything. No bent pins, but the speed of the lane is always x2.

[Jiaszzz_ROG]

Hello @hodjaev_ruslan 

We apologize for the delayed response due to the recent local holiday.

Based on your description, the current SSD installation is as follows: M.2_1: Samsung 990 Pro, M.2_2: Samsung 980 Pro, M.2_3: ADATA XPG Spectrix S40G.
And when cross-testing, the Samsung 990 Pro works correctly in M.2_3, but the ADATA XPG Spectrix S40G is not recognized when installed in M.2_1.

May I ask if any of the SSDs are connected using extension cables or adapters?
How did you verify the operating speed of the Samsung 990 Pro, and does the slowdown only occur in specific scenarios, such as during heavy read/write operations?
We recommend checking that the BIOS version, SSD drivers, and firmware are all updated to the latest versions, and then clearing CMOS to see if the issue persists.
Alternatively, you can remove all SSDs/HDDs and test each one individually to isolate the potential problem.

Thank you.

[hodjaev_ruslan]

I took the motherboard to a repair shop for a check, they had an identical motherboard to try it out, and the one they had was working perfectly fine, mine turned out to be faulty.

I tried to take it back to the store I have purchased it from, but my warranty was cancelled because the motherboard had a bent pin (factory defect as well), but the seller blamed me for that and didn't want to cooperate. Now I'm stuck with a faulty motherboard and no warranty.

[Jiaszzz_ROG]

Hello @hodjaev_ruslan 

Generally, the officially authorized or cooperative retailer will provide an explanation and results after inspection.
Due to the confirmation of personal information involved in the repair process, if you have any concerns, please DM me and share the motherboard serial number and related records from the reseller (such as photos, emails, or conversations).

Thank you.