The new Nvidia SoC incorporates 72 graphics cores and supports a maximum resolution of 3,200-x-2,000 pixels according to Tegra 4 tech specs published on Nvidia's website. Tegra 3's GPU packs 12 graphics cores and tops out at 2,048-x-1,536 pixels. But, neither device will drive an external monitor at those resolutions. For connecting to an external display, Microsoft provides a proprietary "HD video out port" with a maximum resolution of 1,920 x 1,080. The $40 adapter is sold separately. Both Surface models are built around a 10.6-inch five-point touch display with Microsoft's "ClearType" sub-pixel rendering technology. The Surface 2's panel boosts resolution to 1,920 x 1,080, which is just shy of 208 pixels per inch (ppi). The older Surface displays 1,366-x-768 pixels, or 148 ppi.