Abstract: A low profile personal computer includes an enclosure having a bottom wall. A riser card including functional circuitry extends vertically from the bottom wall and partitions the enclosure into first and second regions. A motherboard is positioned within the first region of the enclosure along the bottom wall and adjacent to the riser card for interfacing with the riser card. A series of horizontal option card interfaces are located above each other on the riser card within the first region of the enclosure each for interfacing with a corresponding option card and to position the option cards horizontally over the motherboard. The horizontal option card interfaces are capable of interfacing with a maximum of three option cards at the same time. The functional circuitry on the riser card minimizes the number of option cards which enables the overall height of the enclosure to be minimized.

Abstract: A filler plate for filling an option card slot in a computer enclosure includes a cover plate portion for substantially covering the option card slot. The cover plate portion has a first end and a second end opposite to the first end. A tongue extends from the first end of the cover plate portion for insertion into a capture slot located in the enclosure adjacent to the option card slot to secure the first end of the cover plate portion to the enclosure. First and second retaining tabs extend substantially perpendicularly from the cover plate for engaging first and second edges of the option card slot to hold the filler plate in position relative to the option card slot.

Abstract: A circuit board retainer for use within an enclosure for guiding and securing a circuit board within the enclosure includes a guide portion having an upper rail and a lower rail extending along an edge of the circuit board retainer forming a slot therebetween for guiding a side of the circuit board. A latching portion positioned adjacent to the guide portion engages an ejector lever pivotably connected to the circuit board. The ejector lever is capable of locking the circuit board in place relative to the circuit board retainer.