NVIDIA revealed that Kal-El, the third-generation Tegra chip, will feature a fifth core to enhance energy efficiency. Just like the four regular cores the fifth core is an ARM Cortex A9-based companion core, but it's manufactured on a low-power process and intended to run up to 500MHz only. According to NVIDIA, the companion core enables power savings of 14 to 61 percent compared to Tegra 2. Full details about the fifth core and more new features of Kal-El can be found in these two whitepapers on NVIDIA's blog.
The first whitepaper outlines the patented fifth core. This extra core
