Computer system for multi-type DRAM support

A computer system with DDRAM and SDRAM support comprising:

• a motherboard having a first surface and a second surface;
• a first slot, mounted on the first surface of the motherboard, used for receiving the DDRAM, the first slot having a plurality of first slot pins, each first slot pin corresponding to a first pin assignment, wherein the first pin assignments are categorized under a plurality of pin assignment groups;
• a second slot, mounted on the first surface of the motherboard, used for receiving the SDRAM, the second slot having a plurality of second slot pins, each second slot pin corresponding to a second pin assignment, wherein the second pin assignments are categorized under said plurality of pin assignment groups;
• a plurality of conducting routes;
• a north bridge chip having a plurality of chip pins, mounted on the first surface of the motherboard, connected to the first slot and the second slot through the conducting routes, each chip pin corresponding to a first pin assignment and a second pin assignment, wherein the first pin assignment and the second pin assignment are categorized under the same pin assignment group;
• and
• a control circuit, mounted on the first surface of the motherboard, connected to the north bridge chip, used for defining the pin assignments of the chip pins;
• wherein, when the control circuit inputs a first control signal to the north bridge chip, the pin assignments of the chip pins are set as the first pin assignments so as to enable a data transfer between the north bridge chip and the DDRAM, and when the control circuit inputs a second control signal to the north bridge chip, the pin assignments of the chip pins are set as the second pin assignments, so as to enable a data transfer between the north bridge chip and the SDRAM.