Samsung 128GB DDR5 4800MHz PC5-38400 ECC RDIMM 4Rx4 2S2Rx4 (EC8 10x4) Quad Rank 1.1V Registered DIMM 288-Pin Server RAM Memory M321RAGA0B20-CWK, 1 Module
Bottom line: The Samsung 128GB DDR5 4800MHz PC5-38400 ECC RDIMM 4Rx4 2S2Rx4 is a specs-and-price decision rather than a crowd-consensus one in the memory & ram category, priced around $4,990.00 on Amazon as of 2026-10-21 04:14 UTC. Check the specification table below against one or two close alternatives — on price and spec fit, not on star ratings.
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*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.
Pros & Cons
Pros
- ✓ Samsung DDR5 Memory RAM | Part Number: M321RAGA0B20-CWK
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, shipping and returns are set by the retailer and may have changed since this page was last updated
Manufacturer description
Brand:SamsungPart Number:M321RAGA0B20-CWKMemory Type:DDR5Memory Size:Single 128 GB ModuleForm Factor:DIMM ( 288 Pin )ECC Type:ECC-RDIMM ( Registered DIMM )Speed:4800 MHz (PC5-38400/PC5-4800)Rank:4Rx4 2S2Rx4 (EC8, 10x4), Quad Rank x4Voltage:1.1VCompatible for Server systems ONLY; NOT COMPATIBLE with Desktop Computers, Laptop Computers, or PCs of any kind
SpecPicks Verdict
SpecPicks scored Samsung 128GB DDR5 4800MHz PC5-38400 ECC RDIMM 4Rx4 2S2Rx4 (EC8… using a rating × review-volume × price-fit model applied to published specs and reviews across the memory & ram category. Compare with similarly-priced alternatives in the memory & ram category before committing. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for memory & ram of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- Samsung DDR5 Memory RAM | Part Number: M321RAGA0B20-CWK
- Single 128 GB RAM Module; DDR5 DIMM 288-Pin; Speeds up to 4800 MHz, PC5-38400 (PC5-4800B)
- ECC Registered RDIMM; 4Rx4 2S2Rx4 (EC8, 10x4); JEDEC DDR5 standard 1.1V
- Compatible for select Server systems ONLY; NOT COMPATIBLE with Desktop Computers, Laptop Computers, or PCs of any kind
- Note: EC8 (10x4) ECC Registered modules cannot be mixed with EC4 (9x4) ECC Registered modules or with different ECC types such as ECC Unbuffered, ECC Load Reduced or Non-ECC Unbuffered; (Memory compatibility can vary among different system models and their installed components; please verify compatibility and follow memory channel guidelines to ensure maximum performance)
- Expands your system's available memory resource improving performance, reducing bottlenecks, and increasing workload capacity
Full Specifications
| Brand | Samsung |
|---|---|
| Voltage | 1.1 volts |
| RAM Size | 128 GB |
| Model Name | Trident |
| Form Factor | DIMM |
| Memory Speed | 4800 MHz |
| Model Number | M321RAGA0B20-CWK |
| Item Type Name | computer-internal-memory |
| Number of Pins | 288 |
| Mfr Part Number | M321RAGA0B20-CWK |
| Number of Items | 1 |
| Memory Generation | DDR5 |
| Compatible Devices | Server |
| Data Transfer Rate | 38400 megabytes_per_second |
| Memory Form Factor | RDIMM |
| Additional Features | Ecc |
| Computer Memory Size | 128 GB |
| Warranty Description | Limited Lifetime Warranty covering defects in materials and workmanship |
| RAM Memory Technology | DDR5 |
| Column Address Strobe Latency | 40 |
Ready to buy?
Samsung 128GB DDR5 4800MHz PC5-38400 ECC RDIMM 4Rx4 2S2Rx4 (EC8 10x4) Quad Rank 1.1V Registered DIMM 288-Pin Server RAM Memory M321RAGA0B20-CWK, 1 Module is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.
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