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Green bare DDR4 RDIMM module 64GB 288 pin

OWC

OWC 64GB DDR4 3200 CL22 ECC Registered RDIMM for Lenovo ThinkSystem SR635 SR655 SR850 SR860

SKU CH-S21A-8V1C9
  • Total capacity64 GB
  • Rated speedDDR4 3200 (PC4 25600)
  • CAS latencyCL22
  • Rated voltage1.2 V
  • Buffer typeRegistered
  • Memory rank2Rx4

Capacity 64GB

  • 64 GB capacity expands server memory headroom
  • DDR4 3200 speed delivers high bandwidth throughput
  • ECC registered design protects data integrity
  • 2 V operation reduces power consumption
  • Validated for Lenovo ThinkSystem SR635 SR655 SR850 SR860

Capacity and Compatibility

This 64GB DDR4 ECC Registered RDIMM is built for Lenovo ThinkSystem SR635, SR655, SR850 and SR860 servers. It targets administrators upgrading memory capacity in those specific platforms. Buyers who need unbuffered memory for desktop or consumer workstations cannot use this module.

Speed and Voltage Limits

The module runs at DDR4 3200 (PC4 25600) with CL22 latency at 1.2V. JEDEC compliance ensures operation within that rated speed and voltage envelope. Systems that require faster data rates or lower latency timings will not benefit beyond this specification.

Pre-Installation Checks

Verify the server model matches the listed ThinkSystem variants and that the memory slots accept 288-pin Registered DIMMs. Existing modules must also be ECC Registered; mixing with unbuffered memory is not supported. Confirm the platform uses Xeon SP Gen 2 processors for SR850 and SR860 compatibility.

How it compares

Measured against everything we stock in Model-Specific Memory Upgrades, at today’s prices. Recalculated every night.

Price $367.99
Typical for this category: the median of 21,161 items is $397.99.
Total capacity 64 GB
Higher than about 60% of the 20,941 comparable items (median 32 GB).
Price per GB $5.75 per GB
Cheaper than about 68% of the 20,941 comparable items (median $8.19 per GB).

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Specifications

Product
Brand nameOWC
Part number3R2D42R464 GB
Total capacity64 GB
Product type288-Pin DDR4 ECC RDIMM
Performance
Rated speedDDR4 3200 (PC4 25600)
Memory
CAS latencyCL22
ECC supportYes
Buffer typeRegistered
Memory rank2Rx4
Heat spreaderNo
Power
Rated voltage1.2 V
Compatibility
Compatible systemsLenovo ThinkSystem SR635
Lenovo ThinkSystem SR655
Lenovo ThinkSystem SR850 (Xeon SP Gen 2)
Lenovo ThinkSystem SR860 (Xeon SP Gen 2)

Other versions of this model

5 more in the same range

Questions about this item

Should I pick a single 64GB module or combine smaller DIMMs for the ThinkSystem SR635?

A single 64GB DDR4 3200 CL22 registered ECC RDIMM fills one slot and matches the server's qualified configuration; adding smaller DIMMs would require matching rank, voltage and speed exactly.

What does the 3200 MT/s rating deliver inside a Lenovo SR850 Xeon SP Gen 2 system?

The module runs at DDR4 3200 (PC4 25600) with CL22 latency at 1.2V, providing the maximum JEDEC-standard throughput the platform's memory controller supports for registered ECC DIMMs.

Does the 288-pin DDR4 RDIMM interface limit total memory capacity on the SR655?

The 288-pin registered ECC RDIMM fits the SR655's DDR4 slots; total capacity is capped by the server's maximum DIMM count and the CPU's memory controller, not by the module's pinout.

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