Supermicro X11SSM-F fails to boot if SSDs are installed

Hello and thanks for the help,

System:

Motherboard:	Supermicro X11SSM-F Rev 1.01 with BIOS v3.3 (05/20/2024) (USED)
CPU:			Intel Xeon E3-1275 v5 Quad Core 3.6 GHz with 4.0 GHz Turbo (USED)
RAM:			64GB Kingston 2133MHz DDR4 (ECC) (USED)
Power Supply:	Seasonic FOCUS V3 GX-1000 1000W 80+ Gold ATX Fully Modular PSU (NEW)
Case:			Fractal Design Node 804 Micro-ATX Computer Case (Windowed, Black) (NEW)
Add-on card:    Supermicro AOC-SLG3-2M2 with two 64GB Optane M.2 NVMe SSDs (NEW)
No Hard Drives installed yet

Problem: My Supermicro X11SSM-F BIOS fails to boot if its NVMe M.2 SSD memory is installed.

I’m using a Supermicro AOC-SLG3-2M2 memory add-on card to add two Intel 64GB Optane NVMe M.2 SSDs to my Supermicro X11SSM-F motherboard.
According to the Supermicro website, my motherboard is compatible with this memory add-on card: <FORUM tool won’t allow me to add the “Supermicro AOC-SLG3-2M2” documentation link>

The documentation for the Supermicro AOC-SLG3-2M2 add-on card suggests the following changes to the motherboard BIOS:

Depending on the system, motherboard, and BIOS version, the following BIOS
settings may be necessary for the proper operation of M.2 NVMe drives:
• Having the CPU IOU settings set to x4x4x4x4 PCIe bifurcation. This option may
  be found under BIOS Setup -> Advanced -> Chipset Configuration -> North
  Bridge -> IIO Configuration -> CPU Configuration -> IOU Setting -> x4x4x4x4.
• Having the NVMe Firmware Source set to AMI Native Support. This option may
  be found under BIOS Setup -> Advanced -> PCIe/PCI/PnP Configuration ->
  NVMe Firmware Source -> AMI Native Support.

So I upgraded the motherboard BIOS to the latest version (v3.3, dated 05/20/2024),
reset the CMOS memory, and set the following BIOS options:

  • Advanced tab->Chipset Configuration->System Agent (SA) Configuration->PEG Port Configuration->SLOT7 Bifurcation=[x4x4]
  • Advanced tab->PCIe/PCI/PnP Configuration->NVMe Firmware Source=[AMI Native Support]
  • Save & Exit->Save Changes and Reset

Then I installed the Supermicro AOC-SLG3-2M2 add-on card into SLOT7.
(My motherboard BIOS offers bifurcation only on SLOT7. So I’m using SLOT7 for the memory add-on card.)

Bootup fails with:

0x08=mrcWriteLevelingError    02

and

5 short beeps, 1 long beep

indicating a “memory error”.

The motherboard boots if this memory card is not installed. But fails to boot if it is installed.

What am I doing wrong?

I’d appreciate any help.

For future readers, I found the problem.

The optane m.2 NVMe is only PCIe 3.0 x2 (2 lane):
https://www.intel.com/content/www/us/en/products/sku/135581/intel-optane-memory-m10-series-16gb-m-2-80mm-pcie-3-0-20nm-3d-xpoint/specifications.html

The Supermicro x11ssm-f motherboard bifurcation is PCIe x4 (4 lane). Its BIOS won’t provide x2 or x1.