GMA 950 In MacBook: It's Underclocked ...

We've recently been discussing that the MB would have been a perfect notebook for the mass market if it came with with a real GPU. Unfortunately, Apple decided to use an integrated graphics chipset, the GMA950. Of course graphics performance are really low, but they are even worse than one could expect!! Indeed, Apple has underclocked the GMA950 in the MB — instead of running at 400MHz, it is clocked at 250MHz, as confirmed by a Apple TechNote.
So just like the Radeon X1600 in the MB Pro 15", Apple has decided to underclock GPUs to preserve battery lifespan and to limit, as much as possible, heat generation. It can also explain why the MB was delivering such poor performance in 3D benchmarks.
JCJ