Personal computer with shielding of input/output signals

A microcomputer having a high speed system processor compatible with application programs and operating system software designed to execute on slower speed system processors and comprising:

• a chassis for mounting a planar board and having a base, a front panel and a rear panel, and at least portions of said chassis being maintained at a system ground for dissipation of electromagnetic interference,
• a multilayer planar board mounted on said chassis for interconnecting operating components of the microcomputer and having a side edge portion extending adjacent one of said front and rear panels, interior layers of said planar board defining adjacent said side edge portion conductive pathways for input/output signals flowing to and from the operating components of the microcomputer,
• a high speed microprocessor having a real and protected mode of operation electrically connected with said planar board and coupled to a high speed data bus;
• non-volatile memory electrically connected with said planar board and coupled to a slower speed data bus;
• a bus controller electrically connected with said planar board for providing communications between the high speed data bus and the slower speed data bus;
• volatile memory electrically responsive to the high speed data bus;
• a memory controller electrically coupled to said volatile memory and said non-volatile memory, said memory controller regulating communications between said volatile memory and said high speed microprocessor;
• a cover for engaging said chassis and forming with said chassis a shielded, enclosed volume for containing said microprocessor, memory and controller components of the microcomputer,
• at least one connector mounted on said planar board for passing input/output signals to and from said conductive pathways, and
• a shielding structure having two elements, each of said elements functioning for (i) shielding against adverse effects otherwise possibly arising from passage of input/output signals to and from said conductive pathways and (ii) structurally reinforcing said side edge portion of said multilayer printed circuit board, said shielding structure being operatively connected to a portion of said chassis connected to a system ground and substantially enclosing a region through which said input/output signals pass between said conductive pathways and said panel.