IBM 512MB PC2-4200 CL4 NP DDR2 SDRAM SODIMM 0.5GB DDR2 memory module

512MB PC2-4200 CL4 NP DDR2 SDRAM SODIMM PC2-4200 CL4 Non Parity (NP) DDR2 SDRAM SODIMM Memory - Overview
The PC2-4200 CL4 Non-Parity (NP) Double Data Rate Two (DDR2) Synchronous DRAM (SDRAM) SODIMM offerings let you upgrade standard system memory capacity to improve overall system performance. Features and benefits include:
Tested for compatibility on supported ThinkPad notebooks
Maximum data transfer rate of up to 4,264 MBps
200-pin SODIMM with gold-plated leads
Serial presence detect/decode functions