Audition Graphics/UI Issue

Three things come to mind (not in any particular order): Check the setting of graphics hardware acceleration in Preferences>General. Whatever it's set to, try the other and see if that makes any difference. You might find the second thing a little contentious, but my experience of overclocking an i7 wasn't good - any processing benefit was at best marginal (other things slow up processing way more than the processor does) and it made the system generally less stable. Now it runs at the speed Intel said it should, and it's been way more stable. The third thing is to check all of your drivers, to make sure they're all up to date - especially the video driver...