Abstract: The present invention relates to a novel design of a monolithic body computer, and particularly to the monolithic body computer construction which includes a computer main frame, peripheral extension interface, disk drive system and keyboard all assembled within the display unit. Wherein the display control board originally disposed under the image tube in the rear of the rear of the display unit is alternatively disposed vertically at the right side of the image tube, and the original space is used for an assembly case which can contain several assembly cassettes of boards. The assembly cassettes can receive various multifunctional computer and peripheral interface boards, so that the assembly case provides selectivity to define the computer main frame. A hidden keyboard is provided beneath the screen, and a hidden disk drive system is provided on the right side of the screen.