M321R8GA0BB0-CQK: Samsung 64GB DDR5-4800MHz PC5-38400 ECC Registered CL40 2Rx4 RDIMM Server Memory
Also listed as: M321R8GA0BB0-CQKEG, M321R8GA0BB0-CQK00, M321R8GA0BB0 · made by Samsung
The Samsung M321R8GA0BB0-CQK is a 64GB dual-rank (2Rx4) DDR5-4800 registered ECC memory module engineered for data-intensive enterprise virtualization and in-memory SQL database platforms. Operating at standard 1.1V with CL40 latency, it utilizes Samsung 16Gb DRAM dies with an integrated Power Management IC (PMIC) and dual 32-bit subchannels. When sourcing used Samsung DDR5 RDIMMs, verify the authenticity of the Samsung thermal sticker, check the 288-pin edge card for scratches, and ensure all DIMMs in a memory channel share the same rank architecture.
Specifications
| Part number | M321R8GA0BB0-CQK |
|---|---|
| Brand | Samsung |
| Made by | Samsung |
| Type | Memory |
| Other numbers | M321R8GA0BB0-CQKEG, M321R8GA0BB0-CQK00, M321R8GA0BB0 |
| Status | current |
| Capacity (GB) | 64 |
| Speed | DDR5-4800 |
| Rank width | 2Rx4 |
| Generation fit | Intel 4th Gen Xeon Scalable and AMD EPYC 9004 series servers |
About the M321R8GA0BB0-CQK
M321R8GA0BB0-CQK is Samsung's high-capacity 64GB dual-rank (2Rx4) DDR5-4800 registered ECC memory module designed for memory-intensive cloud server workloads. Utilizing 16Gb density DDR5 DRAM dies operating at 1.1V with CL40 timings, it provides the optimal balance of capacity, bandwidth, and thermal dissipation for multi-tenant hypervisors, container hosts, and in-memory databases on Intel Sapphire Rapids and AMD Genoa architectures.
Compatibility
Compatible with enterprise servers supporting DDR5 RDIMMs, including Dell PowerEdge 16G, HPE ProLiant Gen11, Lenovo ThinkSystem V3, and Cisco UCS M7 servers. It requires an Intel 4th Gen Xeon Scalable or AMD EPYC 9004 series CPU. It cannot be installed in DDR4 memory slots due to mechanical keying differences. When populating memory channels, install in matched pairs or octets across all memory channels per CPU socket for optimal memory interleaving.
How to identify a genuine unit
A genuine module features a Samsung label displaying part number M321R8GA0BB0-CQK, specifications 64GB 2Rx4 PC5-4800B-RC0, and a 2D matrix barcode. Both sides of the PCB are populated with Samsung DRAM packages with a PMIC controller in the center. In iDRAC, iLO, or XClarity, the module is recognized with Samsung manufacturer ID and verified JEDEC SPD profile data.
Buying used
When procuring pulled 64GB modules, test every unit thoroughly using multi-threaded memory stress tests. Inspect the gold edge contacts and ensure the SPD EEPROM chip has not been altered or reprogrammed. Verify that all modules in your order share identical rank structure (2Rx4) to prevent channel downclocking.
Reference prices (last 14 days, updated 2026-10-27)
New: USD 240 (1 sighting, Oct 2026)
Used: USD 160 (1 sighting, Oct 2026)
All sightings
| Seller | Condition | Price | Note | Seen |
|---|---|---|---|---|
| serversupply.com | new | USD 240 | 2026-10-27 | |
| ebay.com | used | USD 160 | 2026-10-27 |
Prices seen on public listings on the dates shown, before tax and shipping. Not an offer.
Fits these models
Equivalent part numbers
- Lenovo 4X77A77496 ThinkSystem 64GB TruDDR5 4800MHz (2Rx4 1.1V) RDIMM ThinkSystem 64GB TruDDR5 4800MHz 2Rx4 RDIMM
- Dell AB949335 Dell 64GB DDR5 4800MHz 2Rx4 RDIMM
FAQ
What is the rank organization of M321R8GA0BB0-CQK?
Dual rank by 4 (2Rx4).
Does this module require 1.1V or 1.2V?
It operates at standard JEDEC DDR5 1.1 Volts.
Buying or selling M321R8GA0BB0-CQK?
New, refurbished or used. Tell us the quantity and condition and we connect you with a vetted reseller in your region, usually within one working day.
Sources
- Samsung Semiconductor DDR5 RDIMM Product Catalog, checked 2026-10-27