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Green 240-pin DDR3 DIMM with black memory chips and gold contacts

Crucial

Crucial CT51272BA186DJ 4GB DDR3 1866 ECC Unbuffered Server RAM

SKU CH-EXKT-SMQ4V MPN CT51272BA186DJ

A 4GB DDR3 1866 ECC unbuffered DIMM with CL13 latency and 1.50V operation for server memory upgrades

  • Capacity4GB
  • Type240-Pin DDR3 SDRAM
  • SpeedDDR3 1866 (PC3 14900)
  • CAS LatencyCL13
  • Voltage1.50V
  • ECCYes
  • ECC protection guards data integrity with 72-bit error correction
  • 1866 MT/s DDR3 speed moves data faster than 1333 standard
  • CL13 latency cuts wait cycles for quicker response
  • Unbuffered design connects directly to the memory controller
  • 4 GB capacity adds headroom for virtualisation workloads

4GB DDR3 1866 ECC Module

This Crucial CT51272BA186DJ is a 4GB DDR3 1866 ECC unbuffered DIMM built for server platforms that require error-correcting memory. It operates at 1.50V with a CAS latency of CL13 and uses a 240-pin interface. The module is sold new as a single stick ranked 1Rx8.

Upgrade From Slower DDR3

Replacing older DDR3 1066 or 1333 modules with this 1866 speed part increases memory bandwidth where the platform supports it. The jump is worth it when the motherboard and CPU memory controller are qualified for PC3 14900 operation and the system can utilise ECC protection.

Verify 240-Pin DDR3 Slots

Confirm the motherboard has 240-pin DDR3 DIMM slots and a DDR3-enabled chipset before ordering. DDR3 modules will not fit DDR2 or DDR sockets. Ensure the platform accepts unbuffered ECC DIMMs rather than registered or fully buffered types.

Highlights

  • ECC protection guards data integrity with 72-bit error correction
  • 1866 MT/s DDR3 speed moves data faster than 1333 standard
  • CL13 latency cuts wait cycles for quicker response
  • Unbuffered design connects directly to the memory controller
  • 4 GB capacity adds headroom for virtualisation workloads

Specifications

BrandCrucial
ModelCT51272BA186DJ
Capacity4GB
Type240-Pin DDR3 SDRAM
SpeedDDR3 1866 (PC3 14900)
CAS LatencyCL13
Voltage1.50V
ECCYes
Buffered/RegisteredUnbuffered
Rank1Rx8
Multi-channel KitDual Channel Kit
ChipsetMajor Brand Chipset
Heat SpreaderNo
Shipping weight0.07 kg
Package size155 × 122 × 13 mm

Questions about this item

Will the 240-pin DDR3 DIMM fit my server motherboard slot?

The module uses the standard 240-pin DDR3 form factor and requires a motherboard with DDR3-enabled chipset and matching DIMM slots; it will not fit DDR2 or DDR sockets.

What is the correct way to seat the module so the 72-bit ECC path works?

Align the notch on the gold edge connector with the key in the slot, press straight down until both side clips click, and verify the system reports 4 GB at 1866 MT/s with ECC active.

When should I plan to replace this 4 GB DDR3 1866 kit?

Replace it if memory diagnostics report correctable ECC errors that increase over time, if the server fails to POST with the kit installed, or when you upgrade to a platform that no longer supports DDR3.

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