New Asus X870E Strix board - M.2 drive disappearing

[Cheairnyndahl]

Hello, just installed my new Asus X870E-E Strix motherboard, loving it so far. When I initially got in to Windows, all of my drives were present (even the new one that wasn't formatted yet was showing in Disk Management) - I updated everything in terms of latest drivers for the motherboard etc, rebooted and enabled EXPO on my RAM, set to 6000MHz with voltages set, didn't touch any other settings...

And now one of my M.2 drives is not showing up in BIOS or in Windows?  I've tried changing the BIOS setting for Bifurcation to GPU+M.2 mode, that doesn't help.  Any suggestions as to what else I can try?  I have a feeling it's related to the whole thing of the GPU slot & the M.2-2 & M.2-3 sharing bandwidth, but the drive that's in one of them is showing up while the other is not now.
I'm going to try disabling EXPO & see if that helps for some reason... wouldn't make any sense if that was it, but perhaps the BIOS version I'm on is messing something up.

[Psamtik]

To be honest, I thought the same initially as I have plenty of experience of perfectly stable ram on 1 system being a crash fest on another, but if I enter the same settings manually as the DOCP/EXPO setting, it works no problem, with the only difference I can see being it doesn't give you the option for asynchronous clocks, which all things being the same (as far as I can tell) between doing it via the profile and leaving the OC setting on automatic and setting it manually, is that one setting. I even put the ram in another asus board and saved the settings to a text file with EXPO/DOCP set for both a Samsung EXPO and SK Hynix DOCP kit  and then entered them manually on this board to make sure I was not missing anything and with the everything else set to default, and again no issues, but then activate expo/docp, amd the drives do their vanishing trick.

I tweak my ram a fair bit more than those settings I listed, as they are the ones for the Buildzoid video on youtube that are mu default stable profile, so my guess is that its not an OC ram stability issue at all or else manual or automatic with the same settings would have the same results, but they don't.  

[Hipflask]

Yeah that is odd - what kit do you have and board??

[Psamtik]

The Asus X870E-E board obviously, with the B650E-I (before it died and they wouldn't replace it), B650E-F and the X670E-F,. I also have the MSI B650I Edge Wifi thoough I have only used the 7800 kit in that. All using a mix of 7800X3D, 9800X3D and 8700G to test it all with to make sure it wasn't a ram, cpu or m.2 drive issue (all of which are Samsung 990 pro's 5x2TB and 1 4TB)

As for ram I have 3 Corsair vengence RGB kits, 2 2x Samsung 16GB 6000 EXPO, 2x SK Hynix 24GB 6000 DOCP/XMP, 2 2x SK Hynix 32GB 6400 , Team Group 2x SK Hynix 16GB 7800. I have also tried a couple of other kits that have been here since I got the board and its all pretty much the same.

Mind you, with my manual timings I have a rock solid system now with all 6 M.2 and 4XSDD working fine with 2x 24GB kit running at 7000, so I am reasonably fine now. Its more a matter of interest now to me as if this will be fixed as I am really not in the mood for another strip down to RMA another board and being without the PC for 2 weeks (that's how long it took to get a disappointing RMA from the same place last week, sent it on the 28th Jan and got the refund yesterday afternoon and picked up the MSI one) 

[Puuhapete]

There is a new beta bios out.

No mention on NVME issues. 

Version 1103 Beta Version

16.49 MB 2025/02/12

"This BIOS enhances system performance and improves high-capacity memory compatibility. This includes support for 2*DIMM memory configurations, achieving speeds up to 6800MT/s with AEMP enabled.

[Koalabear83]

Went to the retailer, they replaced the motherboard with a new one and they also confirmed it's a Asus problem, likely a Bios update fix. I opened a Asus RMA, now on tier 3 tech support.. this motherboard is not even 30 days old btw.. 😒 🙄 😑 

[AOMi]

I've updated to 1103 Beta BIOS and spent some time to get deper into the problem.
And I've found a source of it.

As a user who expected flexibility from a Hi-End motherboard, I am disappointed by the need to choose between GPU and SSD. X870E Crosshair Hero can't be placed in Hi-End range. It's a mid range motherboard with specifications vs reality inconsistency.
For example, much cheaper X870E Tomahawk can disable USB4 and forward that lanes to M2 GEN5 withoug affecting GPU lanes.

You can't build Hi-End PC with this Hi-End priced motherboard (mine is X870E Crosshair Hero):
1. You can't have max speed videocard with max speed M2's.
2. You can't have max speed videocard with more than 3 M2's.
3. You can't have max speed videocard with more than ONE GEN5 M2.
4. You can have low/mid speed videocard with low/mid speed up to 5 M2's.

I've changed Advanced > Onboard Devices Configuration > "PCIEX16_1 Bandwidth Bifurcation Configuration" to "PCIE 16X Mode" and... 100% of reboots was without M2_2. So I suppose when it was on "Auto Mode" it sometimes select 16X for videocard and sometimes for 8X. And when it selects 16X it disables M2_2 slot. As M2_3 too.
At description of this parameter we can see ... "and disable M2_2 and M2_3".
So if you want full-speed videocard (my current 4070 Ti Super will lose about 3-8% when on 8x with LLVM's - it's more than I can forgive and would be unacceptable when I put 5090 or something more faster in closest future) then you can't use more than 3 M2's.

So, 5 M2's with x8 video, or 3 M2's with x16 video. In reality, this MB's is just for 3 M2's.

From characteristics at product page:
** When you use both PCIEX16_1 and PCIEX16_2, PCIEX16_1 and PCIEX16_2 will run x8.
*** When M.2_3 are enabled, PCIEX16_1 will run x8, and PCIEX16_2 will run x4.
**** When M.2_2 and M.2_3 are enabled simultaneously, PCIEX16_2 will be disabled.

Nothing said about "when you use M2_2 or M2_3 then PCIEX16_x will run x8". Just for M2_3 single (16_1 will run x8) and M2_2+M2_3 simultaneously (16_2 will be disabled). When I've bought this MB I read that and it was acceptable, I don't need PCIEX16_2. I payed for other specs. Other boards from other brands disables USB4 populated lanes and not videocard lanes. I don't need USB4 but I need max videocard speed.

24 PCI-lanes from Ryzen 9000 CPU can be divided as PCIEX16_1 x16, M2_1 x4, M2_2 x4 (total 24) and M2_3 with PCIEX16_2 and 1xUSB4 disabled. Why it's not like that??

UPD: found a video on YT that describes everything: youtube.com/watch?v=WKkqlWckseM

UPD2: EXTREMELY BUGGY BIOS/board!
Selecting "GPU with M.2 storage" at Advanced > Onboard Devices Configuration > "PCIEX16_1 Bandwidth Bifurcation Configuration" WILL NOT show M2_2 as connected! Only "AUTO" that is a lottery!

[AlexROG01]

I may have found the solution! I turned off the SATA controller and made sure all my M.2 ports with SSDs were set to the correct PCIe version. My 990 Pro is set to PCIe 4.0, and my T705 is set to PCIe 5.0. Now everything works.

[Psamtik]

If I recall from a diagram I saw recently of how the chipset and CPU lanes are broken down, Its more like 20 free lanes from the CPU as the rest are used for things like the now mandatory USB 4, so you are left with 4 for M.2 and 16 for the PCIe slot,  so only leaving the PCIe slot as the option for splitting (I tried the 2 990 evo drives that I got for my nephews Christmas PC's as I specifically wanted to see if 2 2x pcie 5 m.2 in 1 and 2 would work, which it didn't, still x8) and as the only options are x16 or x8, even one drive will be x8 as the only option. 

I think this board and those like it, is designed around cards like the NVIDIA 50 series that support PCIe 5.0 x8 to get full bandwidth, though that is no help to those of us with no need to upgrade (or money to burn for some of the most minimal improvements for highest price and a feature you can get for a few bucks by buying the Lossless Scaling app) where we are effectively stuck at PCIe 3 x16 speeds (and even then with 2 less drives if you want everything else running as expected). Its a shame that the only thing that makes this board seem attractive, is its biggest Achilles heel as all its other features are barely better than what you got on a mid range MATX board from a couple of years back but for double the price.

[Psamtik]

It seems 1104 has resolved it as promised, all my drives are showing with DOCP 1 and 2, hopefully it works for others with this issue as well. I will be sticking to my manual settings but its nice to see its fixed  for those not wanting to play with ram timings.

[Cheairnyndahl]

I'll be testing it when I get home myself.