The machine with two memory interfaces Model Maximum Capacity and Specification GTR 3550H 32G DDR4 2400MHZ GTR 3750H 32G DDR4 2400MHZ GTR PRO 3550H 32G DDR4 2400MHZ GTR5 5900HX 64G DDR4 3200MHZ GTR4 4900 64G DDR4 3200MHZ SER 3200U 32G DDR4 2400MHZ SER 4800 64G DDR4 3200MHZ SER 3750H 32G DDR4 2400MHZ SEI8 8279U 32G DDR4 2400MHZ SEI8 8109U 32G DDR4 2400MHZ GTi 1135G7 64G DDR4 3200MHZ GTi 1165G7 64G DDR4 3200MHZ U59 16G DDR4 2933MHZ The machine with one memory interfaces Model Maximum Capacity and Specification U57 16G DDR3L 1600MHZ U55 16G DDR3L 1600MHZ GK Mini 8G DDR4 2400MHZ GK55 8G DDR4 2400MHZ GK35 8G DDR3L 1600MHZ