16GB DDR3 Memory Upgrade for Lenovo ThinkServer RD640 Server PC3L-12800 1600MHz ECC Registered Low Voltage DIMM (PARTS-QUICK BRAND) Capacity: 16GB Form Factor: 240 pin ECC Registered DIMM Speed: PC3L-12800R DDR3 1600MHz Voltage: 1.35v Halogen Free; ROHS; Warranty: Lifetime