4 Go de mémoire RAM HP ProBook 4540s (PC3-12800S) compatible RAM - Cdiscount Informatique
HP ProBook 4540s core i3 3rd gen 8GB Ram 250GB HDD Windows 10 Pro 15.6” Screen Laptop with charger in Excellent Working condition!!! Specification: * for Sale in Aurora, IL - OfferUp
Arch Memory 8GB 204-Pin DDR3 1600 MHz So-dimm RAM for HP ProBook 4540s at Amazon.com
HP ProBook 4540s Notebook PC Product Specifications | HP® Customer Support