Yes that fits better

Mainboard - http://en.wikipedia.org/wiki/Motherboard

From WP -

The term mainboard is archaically applied to devices with a single board and no additional expansions or capability. In modern terms this would include embedded systems, and controlling boards in televisions, washing machines etc. A motherboard specifically refers to a printed circuit with the capability to add/extend its performance/capabilities with the addition of "daughterboards".