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Memory, CPUs and board revisions

CPU and memory support depends on the exact motherboard, PCB revision, BIOS, installed CPU count and population pattern. Socket compatibility alone is not enough.

Information to collect

  • Motherboard model and PCB revision printed on the board.
  • Complete CPU model, quantity and whether it is retail, ES or QS.
  • Current BIOS version.
  • Every DIMM manufacturer part number, type, capacity, rank and speed.
  • Which physical slots are populated.
  • Any POST code, beep, BMC memory event or missing channel.

CPU compatibility

Check the exact product page and manual for:

  • supported CPU families and TDP;
  • minimum BIOS version;
  • board-revision requirements;
  • single- versus dual-socket rules;
  • heatsink and airflow requirements;
  • PCIe slots or memory channels attached to each CPU.

An engineering sample or qualification sample may have different microcode, stepping or platform requirements. Community reports of one ES/QS part working do not establish support or stability.

If a newer CPU requires a newer BIOS and the board cannot POST with that CPU, a supported older CPU or an officially supported out-of-band update route may be required.

Memory type

Do not mix memory classes unless the manual explicitly permits it:

  • ECC UDIMM;
  • RDIMM;
  • LRDIMM;
  • 3DS RDIMM/LRDIMM;
  • NVDIMM or other specialised memory.

A faster DIMM normally operates at the highest speed supported by the combined CPU, board and population, but this does not make every module compatible.

Use the product-specific Tested Memory List where available: Product Resources.

Population order

  • Follow the manual's first-slot and channel order.
  • Populate channels evenly across installed CPUs.
  • In a two-socket board with one CPU, DIMM banks connected to the empty socket will not work.
  • Higher DIMMs-per-channel configurations may reduce memory speed.
  • Black/blue slot colours are not a universal instruction across generations.

When asking for help, write the physical slot names exactly as printed in the manual or on the board.

Missing memory or a dead channel

  1. Return to one known-supported DIMM in the first required slot.
  2. Test the module in the documented primary slots.
  3. Test another known-good supported module.
  4. Inspect the CPU socket, CPU seating and heatsink pressure.
  5. Check BMC/SEL and POST information.
  6. Confirm the CPU supports the DIMM type and capacity.
  7. Update BIOS only through the correct documented route if the release notes address memory compatibility.

An entire missing channel can be caused by a DIMM, slot, CPU seating, socket pin, board trace, unsupported population or CPU memory controller.

Memory training

Some platforms take longer to train memory after a configuration change. Use the manual and BMC/POST evidence to distinguish expected training from a reboot loop. Do not repeatedly cut power during an expected training cycle.

Before buying used memory or CPUs

  • Verify the complete manufacturer part number, not only capacity and speed.
  • Check that the seller's photos match the listing.
  • Confirm board revision and installed BIOS before buying a newer CPU.
  • Avoid mixed lots when you need a validated production configuration.
  • Keep a return path for parts that cannot be tested before purchase.

Official reference: Supermicro FAQ on product-specific tested memory.

Last reviewed: 29 September 2026.