Dell Latitude E5440 Laptop Computer, 2.0 GHz Intel i5 Dual Core Gen 4, 4GB DDR3 RAM, 500GB Hard Disk Drive (HDD) SATA Hard Drive, Windows 10 Home 64Bit, 14" Screen (Used) - Walmart.com
parts-quick 8GB Memory for Dell Latitude E5440 DDR3L 1600MHz PC3L-12800 SODIMM Compatible RAM at Amazon.com
Dell Latitude E5440 RAM Memory Replacement. - iFixit Repair Guide