https://bugzilla.kernel.org/show_bug.cgi?id=65761
--- Comment #16 from Alex Deucher alexdeucher@gmail.com --- I'm not familiar with radeon-profile, but if it does some sort of manual polling of the card, it might be waking up the card every time it polls or it might just be reading garbage because the card is powered down. Does it help if you don't run radeon-profile?