ok macrumors people. i noticed this happens on my new powerbook a lot. every once in a while my computer will run really really sluggish with the computer ridiculously hot and fans on full blast. and nothing will stop the CPU from running at full speed. nothing besides restarting. so anyways, it just happened again when i was away from my computer. no programs were running, it was just idling. activity monitor was showing that its running at 100% CPU usage. whats going on?