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Green circuit board with black memory chips and gold edge connector

Computer Memory Solutions

Computer Memory Solutions CM512642400SO 4GB DDR4 2400 CL17 2Rx8 SODIMM memory upgrade

SKU CH-KF6G-N0B73

A 4 GB DDR4 2400 MHz SODIMM module rated CL17 for HP ProBook 640 G3, 640 G4, 645 G4, 650 G3 and 650 G4 laptops

  • Total capacity4 GB
  • Rated speedDDR4 2400 (PC4 19200)
  • ChipsetMajor Brand Chipset
  • CAS latencyCL17
  • Memory timings17-17-17
  • Rated voltage1.2 V
  • 4GB capacity adds responsive multitasking headroom
  • DDR4 2400 speed delivers fast data throughput
  • CL17 latency keeps timing tight for everyday workloads
  • 2V operation reduces power draw and heat
  • Validated for HP ProBook 640 G3, G4, 645 G4, 650 G3, G4

Product identity

This Computer Memory Solutions module is a 4GB DDR4 2400 SO-DIMM built for HP ProBook 640 G3, 640 G4, 645 G4, 650 G3 and 650 G4 notebooks. It targets owners of those specific models who need a single stick to replace a failed module or to add capacity to an empty slot. The kit contains one unbuffered, non-ECC stick with a 2Rx8 organisation.

Capacity and headroom

Each laptop listed supports a maximum of 32GB across two sockets, so this 4GB stick provides a modest increment and leaves room for a second module to reach 8GB or higher. Systems already populated with 16GB or 32GB will not gain usable capacity from adding this stick, and workloads that demand more than 8GB total will still be constrained.

DDR4 SO-DIMM limits

The DDR4 2400 SO-DIMM interface caps transfer rates at 2400MT/s and operates at 1.2V, so this module cannot exceed that speed or voltage envelope. Compatibility is restricted to the named ProBook models; other notebooks, desktops or servers using different DDR generations or pin counts will not accept this stick.

How it compares

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

Price $20.99
Cheaper than about 90% of the 21,161 comparable items (median $397.99).
Total capacity 4 GB
Lower than about 90% of the 20,941 comparable items (median 32 GB).
Price per GB $5.25 per GB
Cheaper than about 73% of the 20,941 comparable items (median $8.19 per GB).

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Specifications

Product
Brand nameComputer Memory Solutions
Model nameCM512642400SO
Total capacity4 GB
Product type260-Pin DDR4 SO-DIMM
Performance
Rated speedDDR4 2400 (PC4 19200)
Processor
ChipsetMajor Brand Chipset
Memory
CAS latencyCL17
Memory timings17-17-17
ECC supportNo
Buffer typeUnbuffered
Memory rank2Rx8
Heat spreaderNo
Power
Rated voltage1.2 V
Compatibility
Compatible systemsHP/Compaq ProBook 640 G3, 640 G4, 645 G4, 650 G3, 650 G4
In the box
Included items1Memory Ram Stick

Questions about this item

Will this 2Rx8 DDR4 SODIMM work alongside the original 1Rx8 module in my ProBook 640 G3?

The module is a 2Rx8 DDR4 2400 CL17 SODIMM; the ProBook 640 G3 supports mixed-rank DDR4 SO-DIMMs, so it will operate with an existing 1Rx8 stick at the lowest common speed and timing.

How can I verify the module is running at DDR4 2400 CL17 after installation?

Open Task Manager or BIOS and confirm the memory speed shows 2400 MHz with CAS latency 17-17-17; CPU-Z SPD tab will also report 2Rx8 organisation and 1.2 V operation.

Does the package contain only the memory stick or are tools and a heat spreader included?

The box includes one 4 GB DDR4 2400 SODIMM; no heat spreader, screwdrivers or additional accessories are supplied.

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