I noticed something funny in cubase. CPU usage does not appear to change between when the song is playing and when it is stopped. So if I load up with plugins and amusing say 50% of my cpu - that remains constant whether playing or stopped. If I bypass plugins - it immediately goes down. I imagine this could cause heat issues (and energy consumption) if you walk away and leave your workstation for a couple hours - the whole time the cpu will be cranking as if it were playing and processing those plugins.