X870E Carbon WIFI - M2_4 SSD randomly not recognized on boot (BIOS/UEFI) - Possible solution too

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nopone156702dd

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I have had the X870E Carbon WIFI motherboard for a few days now. There has been a major problem with the fourth M.2 slot. The NVME SSD in that slot is randomly not recognized on boot. There has not been any issues with the other M.2 slots, only this one. When the drive is recognized during POST, it works normally in the Windows with no problems. When it is not recognized, it appears neither in the Windows as a drive nor as a controller in the Device Manager.

I am using three M.2 SSDs: M2_1 Samsung 990 Pro 4 TB, M2_3 Corsair Force MP600 2 TB, and M2_4 Samsung 970 EVO Plus 1 TB. The second slot M2_2 is not used so that the PCI_E1 bandwidth is not affected. Thus, I cannot say how the M2_2 slot would work.

To guesstimate, the drive in the M2_4 slot is recognized on boot only with like a 10-15 % chance. If it is a warm reboot after not being recognized, the changes are much less. If it is a cold boot from power off, the chances are like that upper range.

I have tried reseating the SSD, switching the order of the SSDs and so on. The problem is with the slot, not any SSD as they work in the other slots. In addition, I have tried different BIOS versions: A21 and A23, and betas A24 and A25. I have tried setting the PCIe Gen versions explicitly for all the drives, and the GPU etc. in the BIOS. Nothing helps. Disabling memory context restore might increase the change of being recognized on warm reboot. It does not matter if the CPU settings are stock without PBO and JEDEC for memory, the issue is the same. And the system passes memory tests and stability tests.

Since the M2_4 slot works through the chipset, I thought it might be the culprit. I tried increasing the Chipset Core Voltage from 1.050 V to 1.150 V. As a result, the system has now detected the drive in the M2_4 slot on every boot since! The Intel NIC in the PCIE_3 should not be affecting the issue although it is also attached via the chipset as it was not installed all the time without improvement. Nevertheless, this modification seems to have resolved the issue.

Main system components:
• Ryzen 9950X CPU
• NVidia RTX 3090 GPU (Gigabyte Aorus Extreme; PCIE_1 slot)
• Corsair 96 GB 6000 MHz CL30 kit (CMH96GX5M2B6000Z30)
• Intel X550-T2 NIC (PCIE_3 slot)
• Samsung 990 Pro 4 TB, Corsair Force MP600 2 TB & Samsung 970 EVO Plus 1 TB
• 4 SATA drives (SSD, DVD-RW, 2xHDD)
• Seasonic Snow White 1050W PSU
• ARCTIC Liquid Freezer III 360 AIO with Thermal Grizzly Conductonaut
 
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i assume your not installing games on all drives, so why not move a drive you use for backup etc, to the second slot, so it wont affect gpu perf.
i had more than one drive not working at full speed (of the slot) when using the 6th slot on mine, while the drive works fine in a different one/external enclosure.

try leaving gen setting to auto, except for gpu slot (highest the card supports) and the switch controlling other pcie lanes (highest gen).
 
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Waldorf said:
i assume your not installing games on all drives, so why not move a drive you use for backup etc, to the second slot, so it wont affect gpu perf.
i had more than one drive not working at full speed (of the slot) when using the 6th slot on mine, while the drive works fine in a different one/external enclosure.

try leaving gen setting to auto, except for gpu slot (highest the card supports) and the switch controlling other pcie lanes (highest gen).
Click to expand...
Well, a major reason I bought X870E Carbon is to be able to use three M.2 SSDs without dropping PCIE_1 to x8 which happens if there is anything installed in the second slot M2_2. As it is a completely new board from the store, just a few days old, the options would either be I return it as defective and go e.g. with Asus ProArt X870E-CREATOR. Instead, this solution of increasing the Chipset Core Voltage seems to have solved it, and currently it seems I do not need to go over the hassle of installing some other motherboard instead.
 
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sure but i havent seen someone using all slots with data transfers at the same time, while gaming/having gpu load, so using all slots its fine.
ignoring you dont saturate the gpu slot even if its just x8, even if you would run it at gen 4 you will likely see gains (vs x16, because of less overhead, virtually every pcie benchmark review shows that.

and if you have issues on usb as well, i would try playing with IOD volt, not SoC.
i havent build/tuned anything past AM4, so maybe have a look at TPU forum, much faster to get help, and many have experience troubleshooting AM5.
 
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Waldorf said:
sure but i havent seen someone using all slots with data transfers at the same time, while gaming/having gpu load, so using all slots its fine.
ignoring you dont saturate the gpu slot even if its just x8, even if you would run it at gen 4 you will likely see gains (vs x16, because of less overhead, virtually every pcie benchmark review shows that.

and if you have issues on usb as well, i would try playing with IOD volt, not SoC.
i havent build/tuned anything past AM4, so maybe have a look at TPU forum, much faster to get help, and many have experience troubleshooting AM5.
Click to expand...

Thanks for the comments and suggestions. I agree that the actual impact of x8 vs x16 is currently small in gaming etc. but affects more GPGPU computations. Even if I accepted the drop of PCIE_1 to x8 and moved M2_4 to M2_2 that would still mean that if and when I would later want to insert a 4th M.2 to the board, I would face the problem again being forced to used the M2_4 that is not recognized properly. In any case, it would be quite hard to accept a non-working M.2 slot in a motherboard with this price tag out of the box. Furthermore, I plan to keep this MB & CPU for a longer time and later change the GPU into a RTX 6090 or 7090 or whatever it will then be then. And those future GPUs might require using the full 5.0 x16 bandwidth for maximal performance. Who knows.

No issues with the USB yet (knock on wood). And regarding the voltages, the key was increasing Chipset Core Voltage that I believe is the "South Bridge" X870E chipset voltage. So related to the CPU package like IOD & Soc, but on the separate chip on the motherboad itself. It is controlling some of the lower speed PCIe 4.0 etc. peripherals such as these PCIE_3 and M2_3 and M2_4.

I just hope that if someone faces similar problems this finding of mine increasing the Chipset Core Voltage could help. And perhaps MSI would take this into account in the future BIOS versions if the issue is more widespread and increase the default voltage accordingly. As I was researching the problem, I saw many posts with M.2 detection problems with other motherboards, but this solution was not found anywhere. Of course, most problems are likely due to improper installation with poor contact, malfunctioning M.2 drive etc. But not in this case.
 
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i still say try swapping it with two of the other (non OS) drives, just to see if its happening as well.
sometimes there is nothing wrong (hw wise), just parts not working together.
 
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Waldorf said:
i still say try swapping it with two of the other (non OS) drives, just to see if its happening as well.
sometimes there is nothing wrong (hw wise), just parts not working together.
Click to expand...
I actually did, as I mentioned in the OP about switching the order of the SSDs. I tried different permutations for the SSDs in M2_1, M2_3 and M2_4, which was quite a pain as the GPU had to always be removed from the way causing unnecessary wear and tear on the PCIE_1 slot too. I think those PCIE-slots are not meant for a very large number of insertions even. The conclusion was that the drives always worked in M2_1 & M2_3. Only the drive in M2_4 would not be recognized. So, it is not the SSD but the slot that is behaving so. And that voltage increase helped for it.
 
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