Abstract:
According to the present invention, a memory expanding device has a module comprising a main memory device and a sub memory device. The main memory device is connected to the outside through an optical interface. The sub memory device is connected to the outside through an electric interface. Through this, if the power consumption is reduced using a high-speed optical interface technique, the high-speed link of a bandwidth used in the main memory device such as a DRAM etc., is supported and a high-capacity main memory device existing in an external device is directly applied to a CPU. Also, personal information and data are portable by mounting the sub memory device of a module type on an external part.