You can query the CPU load at any time from the admin menu.
CPU load will
**usually ** be the sum of the fixed costs of all units in use (plus ~3% of overhead). A unit’s cost does not depend on where you insert it except to the extent that mono vs stereo might affect it. In general expect, a stereo unit's cost to be from 50% to 100% more than its mono version.
In general, units are designed to have a fixed CPU cost that does not depend on their inputs. The cases where this is violated (in order of severity) are: