AnandTech's Ryan Smith reports that the iPad Air 2's A8X GPU is "even better than I thought":
As far as performance is concerned this doesn’t change our initial conclusions – iPad Air 2 performs the same no matter how many GPU clusters we think are in it – but it helps to further explain iPad Air 2’s strong GPU performance. With 256 FP32 ALUs Apple has come very close to implementing a low-end desktop class GPU on a tablet SoC, and perhaps just as impressively can sustain that level of performance for hours. Though I don’t want to reduce this to a numbers war between A8X and NVIDIA’s TK1, it’s clear that these two SoCs stand apart from everything else in the tablet space.
Akin to becoming a camera company, Apple's a leading chipmaker: not only are they responsible for the A-series SoCs that power iOS devices, but they're also designing custom silicon to drive 14.7 million pixel displays. It's impressive.
This is the sort of power you wield when you have a $155 billion war chest.