Modular personal computer

Claim 1

A modular personal computer, comprising: a base system unit including a support frame having a front support plate and a rear support plate, the rear support plate being spaced from the front support plate, at least one structural beam connecting the front support plate to the rear support plate, a power supply mounted within the base system unit, a control panel mounted to the base system unit, and one or more disk drives selected from the group consisting of hard drives and floppy drives attached to the base system unit; a main circuit board assembly configured to mount adjacent to the base system unit, and including a subassembly plate having front and rear edges, a front subassembly panel having an orifice therethrough attached to the front edge of the subassembly plate, a rear subassembly panel having a plurality of orifices therethrough attached to the rear edge of the subassembly plate, at least one front expansion board guide attached to the front subassembly panel, at least one rear expansion slot attached to the rear subassembly panel, a main circuit board removably mounted to the subassembly plate, at least one expansion card having front and rear end removably connected to the main circuit board whereby the front and rear ends of the expansion cards removably connect to the front expansion board guides and to the rear expansion slots, respectively, when the main circuit board is mounted to the subassembly plate, the main circuit board assembly further including an input/output board having an input/output cable mounted to the subassembly plate, a speaker assembly having a speaker cable and a fan assembly having a fan cable mounted in the orifice of the front subassembly panel, and a battery pack having a battery pack cable, and a keyboard cable mounted to, and extending through respective orifices in, the rear subassembly panel; and a cover for removably covering the base system unit and the main circuit board assembly.