Can IP cards (CTI-Link, IP-Ext16 and IP-GW16) be disabled and removed from system without powering down the system? I've removed extension cards without powering down but can not remember about the IP cards.

Oops, should have mentioned that it is a TDA-600

All cards can be disabled and removed without powering down, except the KX-TDA0480 (old, first version IP trunkcard) and of course the MPR.