The empty section in front of the power supply normally housed one or two floppy disk drives, placed on their side so the slots were vertical.

Although a few logic circuits were on the motherboard, primarily for I/O functions, both the processor and the memory resided in separate daughterboards.

[7] The Horizon found a niche in University environments where its inbuilt S-100 bus could be used to interface it to a variety of control systems.

[8] North Star released a hard disk version, with an internal full height 5MB MFM drive.

They also released an S-100 card with integrated memory and two serial ports which allowed up to eight users on one Horizon, each with their own CPU sharing the disk and other resources.