Of course, some people also think that external ram is unnecessary, because the ram in laptop is usually replaceable. First of all, a ddr3 laptop ram module can’t physically fit into a ddr4 laptop ram slot and vice versa. G.SKILL DDR4 Achieves Memory World Record at 4795.8MHz The ddr3 usually offers a transfer speed of up to 14.9gbs/second. Can i use ddr3 ram in ddr4 slot laptop . Ram, type, not the graphics card memory type. Can i use a ddr5 graphics card on ddr2? The ddr3, ddr5 of a graphics card is the vram type/version it has. It is both backward and forward incompatible, so you can't fix it on a ddr4 or ddr2 ram slot. First of all, a ddr3 laptop ram module can’t physically fit into a ddr4 laptop ram slot and vice versa. The choice of ram available to you is pretty exhaustive nowadays. Notches on the connectors of memory sticks are on different places. Ddr3 is a single voltage capable memory dimm, which supports 1.5v operation only. There are ddr3 ram chip...