ECC UDIMM DDR4-2666 PC4-21300

This page lists DDR4-2666 PC4-21300 ECC Unbuffered DIMM (ECC UDIMM) — 288-pin, 1.2V, ECC error correction without a register, for entry servers, workstations and NAS that run unbuffered memory. DDR4-2666 runs at 2666MT/s (2666MHz data rate) for 21.3 GB/s of bandwidth per channel.

What is on this page

Single modules from 4GB to 32GB (4GB, 8GB, 16GB and 32GB), in 1Rx8, 1Rx16 and 2Rx8 rank configurations, plus matched kits up to 256GB total. Use the Module Density, Kit and Rank filters to narrow the list, or Shop by System Model to jump straight to modules matched to a specific machine.

Where DDR4-2666 ECC UDIMM is used

DDR4-2666 ECC UDIMM is commonly paired with Intel Xeon E-2100/E-2200 platforms, Supermicro X11 boards, Lenovo and Dell entry towers, and Synology DiskStation and RackStation NAS. On this page the system-matched listings cover Intel server boards, Synology, Dell, Lenovo and ASUS. ECC unbuffered memory is only recognized as ECC on boards and CPUs that support it; on a non-ECC board it runs as standard memory.

Choosing the right ECC UDIMM module

ECC UDIMM is unbuffered — it cannot be mixed with RDIMM or LRDIMM, and platforms that take ECC UDIMM typically cap out at two modules per channel. Check the board's qualified memory list for maximum module density; many DDR4-2666 entry platforms support 32GB per slot but not 64GB. Match speed and rank to installed modules when adding rather than replacing. If you are unsure, send us the system model or the OEM part number and we will confirm fitment before you order.

Buying DDR4-2666 ECC UDIMM direct from NEMIX RAM

NEMIX RAM is a US-based server memory specialist since 1993. Every module is researched, matched and compatibility-tested by NEMIX RAM, JEDEC-compliant, and backed by a lifetime warranty. Purchase orders, net terms and volume pricing are available for business, government and education buyers — request a quote with the part numbers or system models you need, or contact our sales team for fitment help.

Related: all ECC UDIMM memory · ECC UDIMM DDR5-5600 · ECC UDIMM DDR5-5200 · ECC UDIMM DDR5-4800 · ECC UDIMM DDR4-3200 · ECC UDIMM DDR4-2933 · ECC UDIMM DDR4-2400 · ECC UDIMM DDR4-2133 · ECC UDIMM DDR3-1866 · ECC UDIMM DDR3-1600 · ECC UDIMM DDR3-1333.

Also searched as DDR4-2666, DDR4 2666MHz, 2666MT/s, PC4-21300, 288-pin ECC UDIMM, DDR4-2666 ECC Unbuffered.