For some of us, amid all the hubbub about
revolutions and whatnot yesterday, the most significant announcement on hand was
Apple's supposedly custom A4 CPU. Alas, in the cold and brutal light of the morning after, we're hearing that it is in fact a system-on-a-chip driven by a
Cortex-A9 MPCore CPU "identical" to the one found inside
NVIDIA's Tegra 2, while besting the
iPhone 3GS significantly with its 1GHz speed and multicore architecture. The A4 is composed of that Cortex barnburner, an integrated memory controller, and the
Mali GPU, making it an all ARM affair -- though we still don't know how much Apple and
PA Semi did in terms of arranging and integrating those components within the silicon. While still not 100 percent confirmed, it would seem there were no revolutions on the iPad's processing front -- just a rebranded bit of well engineered hardware.