SAMSUNG 970 EVO PLUS 500GB shows up as M.2 PCIe x2 (Solved)

Hello Colleagues,

I’m in the middle of testing and messing around with my new computer:

  • Ryzen 9, 3950X
  • Gigabyte Aorus X570 Master (came with F4 UEFI but upgraded to latest F11, running failsafe defaults, except I deactivated onboard audio, since I have a separate Creative card)
  • Corsair HX1000i PSU
  • Samsung 970 EVO Plus 500 GB M.2 PCIe SSD. (added recently as an upgrade to my “random 840 EVO SATA drive salvaged from my previous computer”)
  • BeQuiet Dark Base Pro 900 rev 2 case (although probably not relevant to the topic)
  • Noctua NH-D15 Chromax Black cooler
  • 16GB Corsair Vengeance LPX DDR4 memory (CMK16GX4M2B3200C16);

My problem is currently (apart from my RAM troubles - detailed in my other post) that the Samsung 970 EVO Plus drive shows up in HWInfo and in the Samsung Magician SW as PCIe 3.0 @ x2.

I was expecting it to show up as PCIe 3.0 @ x4, and I’m a little puzzled. So, do you guys have some hints:

  • am I expecting too much? (x2 is normal?)
  • is there something in the MB BIOS I need to mess with? (I have not found anything…)
  • what could I do to get it to report right in the HW information programs?

Many thanks in advance,

Edit: useful:
All I would say is try one of the other sockets, even if they are under GPU’s?

Not useful:
It might be some pcie4 thing, but you would have seen in the Bios/UEFI if it was set to pcie4

No should be x4

Check the bios to see if you can manually set the slot to talk in 3.0 and you could try another port as well. (What port do you have it plugged into)

The board is advertised as all m.2’s doing PCIE4x4, but it’s only x570, so I don’t see how they could spare the lanes, and have some left for the regular PCIE sockets

@mutation666: I had a short look in the UEFI; I see no place where I might specifically set the M.2 slot to be any kind of PCIe (3.0 or 4.0, 2x or 4x). The UEFI seems to only inform me of the existence of the drive in a particular M.2 slot, but does not really let me change anything. Also, it says nothing about whether the PCIe is running at 2x or 4x, just that it’s 3.0. The 2x part I see only in HWInfo type programs, otherwise I wouldn’t know better. Also, to your question, I have it mounted in the M.2 slot closest to the CPU, above the GPU. There is an additional M.2 slot below the CPU and then a third one connected to the chipset, sharing bandwidth with the SATA5/6 slots (it seems).

@Trooper_ish: on the X570 Aorus Owner’s thread on there is a link to a google drive file detailing the PCIe organization. Out of that file it looks like it should fit with x4 on the M.2 slot, but I have by no means understood the whole picture, so I could be wrong……PdjQQ3xZwShiAD

@All: anyway, I will try a different M.2 slot (the one just below the GPU) and a reseating and will report back.

What does the benchmark results show? Maybe its just HWinfo being wrong?

Can you try reseating the cpu maybe not making good contact as you have been having quite a few issues with this set up.

Reseating the CPU might be an option at the moment, since I seem to be having both RAM and SSD troubles… but it’s a hassle… I have to dismantle the whole computer…

As it happens, I just ran a benchmark in Samsung Magician, and saved it to compare with the other M.2 slot I will try to use. Here it is:

I’ll report back with Benchmark result once I move the drive to the other slot.

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What PCIe slots are you using, seem to remember that one of the M.2 slots will be x2 if you are using some of the SATA slots because there are not enough pci lanes. One of the M.2 should be directly through the CPU while I think the issue will be with the one going through the chipset instead.

Guessing you didnt make it far enough down yet

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Ahhhh, didn’t see that one no.

So he should be directly wired to CPU, so if he shows up at 4x off the chipset i think it is the mounting of the cpu or the mobo (he is having ram issues too)

I have read the MB manual, and the way I understand it we have:

  • the M.2A slot, closest to the CPU is x2/x4 and connected directly to the CPU
  • the M.2B slot, just below the GPU, is x2/x4 and connected to the chipset
  • the M.2C slot, even lower, is x2/x4 and is connected to the chipset, but shares bandwidth with the SATA5/6 connectors.

So, what I did now is I put the SSD in the M.2B slot, and it shows up as x4 in Samsung Magician and HWInfo. Have also a look at the benchmark result (in the M.2B slot the Random reads and writes are slightly lower than the M.2A slot, but the sequential performance is almost doubled - literally)…

I’ll put the SSD back in the M.2A slot, hoping it was actually a SSD seating problem, and report back… If that’s not it, then I will have to bite the bullet and reseat the CPU.

So going by the results I would put it on your cpu not being properly socketed or bad traces for that first socket on the mobo (could be bad cpu as well but doubt it)

I’ll start with LOLOLOLOLOL. LOL

So I put the SSD back in the M.2A slot (connected directly to the CPU). And guess what: turns out it was a seating problem after all, because now it shows as x4.

And here are the Samsung Magician benchmarks, compared to the previous:

And here is what HWInfo reports:

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I’ll mark my last post as “Solution” since I think it gives a good picture on the performance impact of the various connectivity options for an SSD. Someone else might find that interesting.

I’ll summarize again for easy reference:

  • benchmark at 22:04 is PCIe x2 directly to CPU
  • benchmark at 22:58 is PCIe x4 through the chipset
  • benchmark at 23:36 is PCIe x4 directly to CPU



Did re-seating the cpu fix it.

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Nope, this was fixed before reseating the CPU. Reseating the SSD was sufficient.