Enterprise DDR4 and DDR5 ECC RDIMM memory ranked by live cost per gigabyte: 49 modules tracked, 41 in stock, cheapest DDR4 at $4.92/GB and cheapest DDR5 at $29.37/GB. Samsung, Micron and SK Hynix. Prices refresh on a rolling cycle - every module updates about once a day.
Buying memory capacity for local AI? The budget AI box costs a used-server build from these same live module prices. Shopping one manufacturer? The SK hynix page prices its RDIMMs per gigabyte beside its SSD lines.
DDR4 ECC RDIMM remains the standard for existing Intel Xeon (Ice Lake, Cascade Lake) and AMD EPYC (Milan, Rome) servers. DDR5 ECC RDIMM is required for Intel Sapphire Rapids, AMD EPYC Genoa and newer platforms. Check your server's memory specification before ordering - DDR4 and DDR5 are not cross-compatible.
Every module below passes our live price ranking, but price alone doesn't answer whether a specific module works in a specific server. These pages cover the actual compatibility rules, each cited to the vendor document that states it.
| $/GB ▲ | Brand / Part No. | Capacity | Speed | Type | Rank/Org | Wty | Price | 90D | Buy |
|---|---|---|---|---|---|---|---|---|---|
| 👑$4.92 | SK Hynix HMAA8GL7MMR4N 2 offers | 64GB | DDR4-2400 | RDIMM | — | — | $314.95 | Buy on AmazonDetails | |
| $5.44 | A-Tech M393A2G40DB0-CPB | 16GB | DDR4-2133 | RDIMM | — | — | $86.98 | Buy on AmazonDetails | |
| $6.23 | Samsung M393A8K40B22-CWD | 64GB | DDR4-2666 | RDIMM | — | — | $399.00 | Buy on AmazonDetails | |
| $6.23 | Supermicro B07DFLTWN3 | 64GB | DDR4-2666 | LRDIMM | — | — | $399.00 | Buy on AmazonDetails | |
| $6.41 | A-Tech B0BPN414ZJ | 64GB | DDR4-2666 | LRDIMM | — | — | $410.03 | Buy on AmazonDetails | |
| $7.12 | Samsung M393A2G40EB1-CPB | 16GB | DDR4-2133 | RDIMM | — | — | $113.94 | Buy on AmazonDetails | |
| $7.19 | MICRON MTA36ASF4G72PZ 2 offers | 32GB | DDR4-2400 | RDIMM | — | — | $229.98 | Buy on AmazonDetails | |
| $7.40 | A-Tech B0BPN4FLDX | 32GB | DDR4-2666 | RDIMM | — | — | $236.78 | Buy on AmazonDetails | |
| $8.72 | SK Hynix HMA84GR7CJR4N-VK | 32GB | DDR4-2666 | RDIMM | — | 3yr | $279.00 | Buy on AmazonDetails | |
| $8.75 | Samsung M393A2K43CB2-CTD8Q 2 offers | 16GB | DDR4-2666 | RDIMM | — | — | $139.99 | Buy on AmazonDetails | |
| $8.91 | A-Tech B083Q3F5DX | 32GB | DDR4-2400 | RDIMM | — | — | $284.97 | Buy on AmazonDetails | |
| $8.95 | A-Tech B0BPN4L74H | 32GB | DDR4-2933 | RDIMM | — | — | $286.44 | Buy on AmazonDetails | |
| $9.17 | A-Tech B0CGJFB4TG | 32GB | DDR4-2933 | RDIMM | — | — | $293.42 | Buy on AmazonDetails | |
| $9.21 | Kingston KSM24RD4/32MEI | 32GB | DDR4-2400 | RDIMM | — | — | $294.62 | Buy on AmazonDetails | |
| $10.05 | Samsung M393A4K40CB2-CTD 2 offers | 32GB | DDR4-2666 | RDIMM | — | 3yr | $321.56 | Buy on AmazonDetails | |
| $10.06 | A-Tech B0C2FML23M | 64GB | DDR4-2933 | RDIMM | — | — | $643.61 | Buy on AmazonDetails | |
| $10.33 | A-Tech KTD-PE429 | 64GB | DDR4-2933 | RDIMM | — | — | $661.26 | Buy on AmazonDetails | |
| $10.94 | Kingston KTD-PE426 | 32GB | DDR4-2666 | RDIMM | — | — | $349.99 | Buy on AmazonDetails | |
| $11.25 | Crucial B017UGKB32 | 16GB | DDR4-2400 | RDIMM | — | — | $179.99 | Buy on AmazonDetails | |
| $12.06 | Samsung M393A2K43BB1-CTD6Q | 16GB | DDR4-2666 | RDIMM | — | — | $193.04 | Buy on AmazonDetails | |
| $12.44 | Kingston KSM26ED8/16HD | 16GB | DDR4-2666 | UDIMM-ECC | — | — | $199.01 | Buy on AmazonDetails | |
| $12.50 | Samsung M393A8G40AB2-CWE 2 offers | 64GB | DDR4-3200 | RDIMM | — | 3yr | $800.00 | Buy on AmazonDetails | |
| $13.41 | Samsung M393A2K43DB2-CTD6Y | 16GB | DDR4-2666 | RDIMM | — | — | $214.49 | Buy on AmazonDetails | |
| $13.52 | SK Hynix HMAA8GR7AJR4N-XN | 64GB | DDR4-3200 | RDIMM | — | 3yr | $865.00 | Buy on AmazonDetails | |
| $14.31 | A-Tech MTA36ASF8G72PZ | 64GB | DDR4-3200 | RDIMM | — | — | $916.05 | Buy on AmazonDetails | |
| $29.37 | V-Color B0GYCQNYQ6 | 256GB | DDR5-4800 | RDIMM | — | — | $7,519.99 | Buy on AmazonDetails | |
| $35.08 | Samsung M321R8GA0BB0-CQK 2 offers | 64GB | DDR5-4800 | RDIMM | — | — | $2,245.00 | Buy on AmazonDetails | |
| $39.94 | Samsung M321R2GA3BB6-CQK | 16GB | DDR5-4800 | RDIMM | — | — | $639.00 | Buy on AmazonDetails | |
| $40.62 | Kingston KSM56R46BD8PMI | 32GB | DDR5-5600 | RDIMM | — | — | $1,299.99 | Buy on AmazonDetails | |
| $41.15 | A-Tech B0DMC1VFNS | 96GB | DDR5-4800 | RDIMM | — | — | $3,949.99 | Buy on AmazonDetails | |
| $41.67 | Kingston KSM56E46BD8KM | 48GB | DDR5-5600 | RDIMM | — | — | $1,999.99 | Buy on AmazonDetails | |
| $42.44 | NEMIX MTC20F2085S1RC48BR | 32GB | DDR5-4800 | RDIMM | — | — | $1,357.99 | Buy on AmazonDetails | |
| $42.63 | SK Hynix HMCG88AEBRA168N | 32GB | DDR5-4800 | RDIMM | — | 3yr | $1,364.27 | Buy on AmazonDetails | |
| $44.28 | NEMIX MTC40F204WS1RC56BB2R | 96GB | DDR5-5600 | RDIMM | — | — | $4,250.99 | Buy on AmazonDetails | |
| $44.37 | NEMIX MTC10F1084S1RC56BR | 16GB | DDR5-5600 | RDIMM | — | — | $709.99 | Buy on AmazonDetails | |
| $45.51 | NEMIX MTC40F204WS1RC64BC1R | 96GB | DDR5-6400 | RDIMM | — | — | $4,368.99 | Buy on AmazonDetails | |
| $45.51 | NEMIX MTC40F204WS1RC64BR | 96GB | DDR5-6400 | RDIMM | — | — | $4,368.99 | Buy on AmazonDetails | |
| $45.55 | A-Tech M321R4GA0PB0-CWM | 32GB | DDR5-5600 | RDIMM | — | — | $1,457.64 | Buy on AmazonDetails | |
| $46.14 | Micron MTC40F2046S1RC56BD2 | 64GB | DDR5-5600 | RDIMM | — | 3yr | $2,952.99 | Buy on AmazonDetails | |
| $46.25 | Samsung M321R4GA3BB6-CQK | 32GB | DDR5-4800 | RDIMM | — | — | $1,479.99 | Buy on AmazonDetails | |
| $48.59 | A-Tech B0DYR9JXRH | 64GB | DDR5-6400 | RDIMM | — | — | $3,109.55 | Buy on AmazonDetails | |
| Check availability | V-Color B0GYCHJPHZ | 256GB | DDR5-6400 | RDIMM | — | — | Out of stock | Check availabilityDetails | |
| Check availability | SK Hynix HMCT04MEERA132N | 128GB | DDR5-4800 | RDIMM | — | — | Out of stock | Check availabilityDetails | |
| Check availability | Samsung M321RYGA0BB0-CQK | 96GB | DDR5-4800 | RDIMM | — | — | Out of stock | Check availabilityDetails | |
| Check availability | Samsung M393A8G40BB4-CWE 2 offers | 64GB | DDR4-3200 | RDIMM | — | 3yr | Out of stock | Check availabilityDetails | |
| Check availability | Kingston KSM56R46BD4PMI | 64GB | DDR5-5600 | RDIMM | — | — | Out of stock | Check availabilityDetails | |
| Check availability | Samsung M393A4K40CB1-CRC | 32GB | DDR4-2400 | RDIMM | — | 3yr | Out of stock | Check availabilityDetails | |
| Check availability | Kingston KSM32ED8/32HD | 32GB | DDR4-3200 | UDIMM-ECC | — | — | Out of stock | Check availabilityDetails | |
| Check availability | Kingston KSM32ES8/16MF 2 offers | 16GB | DDR4-3200 | UDIMM-ECC | — | — | Out of stock | Check availabilityDetails |
OEM-verified memory rules per platform, with live compatible-module prices and upgrade math.
ECC detects and corrects single-bit memory errors. Required for servers and workstations running 24/7. Consumer desktops use non-ECC. All modules listed here are ECC.
RDIMM is standard for most 1-2 DIMM per channel configs. LRDIMM allows more DIMMs per channel (4+) at cost of slightly higher latency. UDIMM-ECC suits workstations with ECC-capable CPUs.
DDR5 starts at 4800MT/s vs DDR4's max 3200MT/s. DDR5 uses on-die ECC for improved reliability. Not backward compatible. Requires specific CPU and motherboard support.
Servers require identical DIMMs per channel. Always install in matched pairs. Consult your server's QVL (Qualified Vendor List) before purchasing.
Out of stock on Amazon, or no longer listed. Each page keeps its specifications and points to what is in stock now; none of them has a current price.
51 product pages, 42 with a live offer today. Each page carries the listing's specifications, its condition and provenance, and in-stock alternatives. Prices are on the tables above, not in this index.
Troubleshooting pages that lead here. Each starts with the diagnosis and says whether hardware is the fix.
ECC (Error-Correcting Code) RAM detects and corrects single-bit memory errors automatically. Required for data integrity in servers running 24/7 workloads. A single uncorrected memory error can cause data corruption or kernel panics. All enterprise servers require ECC memory.
No. DDR4 and DDR5 are physically incompatible - different slot notch positions, different voltages (1.2V vs 1.1V), different pin counts. Your server supports only one generation. Check your server's specification sheet.
This indicates rank and chip organization. 2R = dual rank (two independent sets of chips). x4 = each chip is 4 bits wide (more chips, more bandwidth). x8 = each chip is 8 bits wide (fewer chips). Dual rank (2R) modules generally perform better than single rank (1R) for servers.
Samsung, SK Hynix and Micron are the three primary DRAM manufacturers - virtually all server RAM originates from one of these three companies regardless of the reseller brand. Buying direct Samsung/Hynix/Micron OEM modules is recommended for production servers.
Background: why RAM is so expensive in 2026 - the allocation decision behind the price rise, the consumer anchors, and our own measured server index.