Intel's Thomas Piazza, director of the firm's Architecture Group and Graphics Architecture, spoke about the failings of the Larrabee GPU as this week's IDF in San Francisco. Asked about why he thought it had failed, Piazza replied honestly that the project was too impractical to make it work, and he confirmed that Intel ran into performance per watt issues.
When asked why Piazza thought it had failed though he was surprisingly candid. "I just think it's impractical to try to do all the functions in software in view of all the software complexity," he explained. "And we ran into a performance per watt issue trying to do these things."
"Naturally a rasterizer wants to be fixed function." Piazza went on. "There is no reason to have the programming; it takes so little area for what it does relative to trying to code things like that."
It turned out that it was a problem of trying to balance out what they were doing, trying to find "what's the right level of programmability and what's the right level of fixed function."
Unfortunately with the Larrabee project Intel tried to make everything programmable.