HP EliteBook 840G1 Laptop Computer, 1.60 GHz Intel i5 Dual Core Gen 4, 16GB DDR3 RAM, 500GB Hard Disk Drive (HDD) SATA Hard Drive, Windows 10 Home 64Bit, 14" Screen (Used) - Walmart.com
HP Elitebook 840 G1 RAM Replacement - iFixit Repair Guide
Confused - Elitebook 840 G1 and the SSD m.2 slot 42mm - SAT... - Page 2 - HP Support Community - 5085271
CMS 16GB (2X8GB) DDR3 12800 1600MHz Non ECC SODIMM Memory Ram Upgrade Compatible with HP/Compaq® Elitebook 840 G1 - A7 at Amazon.com
MemoryMasters 4GB Memory Upgrade for HP EliteBook 840 G1 DDR3L 1600MHz PC3L-12800 SODIMM RAM at Amazon.com
Memory RAM Upgrade for HP EliteBook 840 G1 4GB/8GB DDR3 SODIMM | eBay
A-Tech 4GB Module for HP EliteBook 840 G1 Laptop & Notebook Compatible DDR3/DDR3L PC3-12800 1600Mhz Memory Ram (ATMS266381B12034X1) at Amazon.com
A-Tech 8GB Module for HP EliteBook 840 G1 Laptop & Notebook Compatible DDR3/DDR3L PC3-14900 1866Mhz Memory Ram (ATMS266381B30845X1) at Amazon.com