In a move that is surely going to raise some eyebrows, Intel has apparently decided to add a pair of HD video decoders to the logic on-board the Larrabee graphics chip; this according to a story over at SemiAccurate.  This would definitely go against the whole premise of the Larrabee architecture: to do as much work as possible in x86 software without the need for dedicated hardware to any one specific task.  Intel said from the beginning that textures required special hardware to run most efficiently but now that Intel has decided HD decoding is too inefficient on the platform, you can’t help but wonder if there are other tasks with the same fate. 

Larrabee now needs HD decoders to keep up - Graphics Cards  1

Is Larrabee going to turn more into a GPU than originally planned?

WORD HAS REACHED our tender ears that Larrabee, the upcoming Intel GPU, will not be quite as generalist as they claim. The fixed function parts will be two HD decoders.

This addition seems like a last minute thing, so it is probably pulled from Intel’s existing IP catalog. The most likely candidate seems to be the G45 decoders, they are small, low power, and have (finally) decent drivers. Then again, does area really matter in a 700+mm^2 chip?

Don’t take this to mean Larrabee is underpowered, it most definitely is not. The GPU can decode HD streams until you get bored watching them, the problem is that it can’t necessarily do so while staying in an acceptable power budget. Having all the cores pump out HD would likely produce enough heat to keep the fans spun way up, and that is death in the HTPC market.