Computer Core - sswelm/KSPInterstellar GitHub Wiki
Computer cores are 3.75m diameter parts that can act as a command module with a small amount of SAS reaction wheel torque. A computer core can be upgraded in-flight with Science to an Artificial General Intelligence (AGI) core capable of performing scientific research, much like a science lab, while retaining command module functions.
If power is available in the form of MegaJoules, an un-upgraded computer core will use 1MW and an AGI core will use 5MW.
Upgrading a Computer Core takes 1200 science and is done on a per part basis. To do so, right-click on the part while the craft is active and the option should appear (or it will show you how much science you have built up towards this option). An upgraded core is necessary for some functionality from KSPI (e.g. the Direct Planetary Observation mission from the IR Telescope).