Thanks to AMD's ZeroCore Power scheme, 7000-series Radeon GPUs switch to an ultra-low-power state when the display is off. The company says power draw for the whole card drops under 3W when that happens. Our findings show idle power consumption does drop dramatically when the display goes to sleep. (Keep in mind that our power consumption measurements apply to the entire system except for the monitor, not just the graphics card.)
No surprises here. The Radeon HD 7870 and 7850 are the most power-efficient of the bunch, but why wouldn't they be? They both have small and nimble 28-nm GPUs, while our other cards must make do with larger, more power-hungry 40-nm chips.
Noise levels and GPU temperatures
None of these cards are terribly loud except for the Radeon HD 7870, whose blower-style cooler spins itself into a frenzy under load. That cooler design does have the benefit of exhausting hot air directly outside the case, which can be particularly helpful in multi-GPU configs. Still, there's something to be said for the large, conventional fans AMD's partners typically put on their cards.
Yeah, so, no need to worry about your shiny new 7800-series Radeon overheating. That kind of thermal headroom should be helpful to overclockers, as well. Speaking of which...