Additionally the A5x was a really expensive chip to produce. It didn't have the graphics power to drive the retina screen so they just threw silicon at it. It

Additionally the A5x was a really expensive chip to produce. It didn't have the graphics power to drive the retina screen so they just threw silicon at it. It had twice the die size as the Tegra 3: http://www.anandtech.com/show/5685/apple-a5x-die-size-measured-16294mm2-likely-still-45nm http://www.anandtech.com/show/5685/apple-a5x-die-size-measur...