Take it with a grain of salt but according to FUD Zilla the upcoming Larrabee GPU from Intel won't have any power-saving features. The site claims Larrabee will use a staggering 300W in 3D games, roughly 200W in 2D apps and still about 100W in idle mode.
Modern GPUs have a wide range of power-saving features that can switch off unused parts of the GPU when you're, for example, just using Windows or when you're watching a movie and this allows for most graphics cards to hit very reasonable power levels in non-3D applications. However, we've been informed by a very reliable source that Intel's Larrabee won't support this kind of feature until the second generation of hardware.
As Fudo reported earlier, the card will draw 300W when it's running 3D applications, but it will draw over 200W doing pretty much anything and it won't be going lower than to about 100W even at idle. It really looks like Intel has messed up here and we'd expect this card to be wasting a lot of power and run quite hot even when it's not doing very much.