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Green circuit board with gold edge connector and black memory chips

OWC

OWC 4GB DDR3 1333 PC3-10600 CL9 2Rx8 204-pin 1.5V Non-ECC SODIMM for ThinkPad W520

SKU CH-Q6SR-KFB3Z

A 4GB DDR3 1333 SODIMM built to JEDEC and ROHS standards for the ThinkPad W520

  • Capacity4GB
  • Type204-Pin DDR3 Non-ECC SODIMM
  • SpeedDDR3 1333 (PC3 10600)
  • CAS LatencyCL9
  • Voltage1.5V
  • ECCNo

Capacity 4GB

  • Boost responsiveness with a 4GB DDR3 1333MHz module
  • JEDEC and RoHS compliant for a warranty-safe upgrade
  • Simple DIY installation fits the 204-pin SODIMM slot
  • Runs at standard 1.5V for broad laptop compatibility
  • 2Rx8 unbuffered design works in ThinkPad W520

System-specific DDR3 SODIMM for ThinkPad W520

This module is a single 4 GB DDR3 SODIMM built to the PC3-10600 1333 MHz CL9 JEDEC standard. It targets owners of a Lenovo ThinkPad W520 who need a straightforward capacity increase without changing voltage or form factor.

204-pin unbuffered non-ECC stick at 1.5 V

The 204-pin edge connector drops directly into the laptop's SO-DIMM slots. Unbuffered, non-ECC organisation and 1.5 V operation match the factory specification, so installation is a simple DIY swap with no BIOS tuning required.

4 GB 2Rx8 density decides fit

A single rank of 2Rx8 chips delivers 4 GB per module; the W520 accepts this density in each slot. Buyers needing more than 4 GB per slot or requiring ECC error correction must choose a different module.

Highlights

  • Boost responsiveness with a 4GB DDR3 1333MHz module
  • JEDEC and RoHS compliant for a warranty-safe upgrade
  • Simple DIY installation fits the 204-pin SODIMM slot
  • Runs at standard 1.5V for broad laptop compatibility
  • 2Rx8 unbuffered design works in ThinkPad W520

Specifications

BrandOWC
Part Number1S3D32R804GB
Capacity4GB
Type204-Pin DDR3 Non-ECC SODIMM
SpeedDDR3 1333 (PC3 10600)
CAS LatencyCL9
Voltage1.5V
ECCNo
Buffered/RegisteredUnbuffered
Rank2Rx8
Heat SpreaderNo
Compatible SystemLenovo ThinkPad W520

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Questions about this item

What does the DDR3 1333 PC3-10600 rating mean for real-world bandwidth?

The module runs at 1333 MT/s with a peak transfer rate of 10600 MB/s; the ThinkPad W520 memory controller caps actual throughput at that ceiling.

Will this 204-pin SODIMM fit the ThinkPad W520 memory slot without modification?

Yes, the 204-pin DDR3 SODIMM form factor matches the W520 slot exactly; no adapter or bracket is needed.

What is the correct insertion technique for this SODIMM, and where do installers usually go wrong?

Align the notch, slide the module in until the gold contacts are fully hidden, then press down evenly until both side clips snap into the notches — the common error is stopping before the clips engage.

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