Norton used to be fine, but that was b4 NAV 2003, at least for me, with Poser 6 I've only had over heating probs that require to cool down the 'puter first b4 trying to use it again, but that's only when I'm using a bunch of figures in the same scene, in most cases the machine suddenly reboot without warning but that's 'cuz I'm using a 2100+ with a standard heatsink . . .