The CPU side of the NVIDIA Tegra K1 SoC is pretty similar to that of the Tegra 4 part. Both parts are based on a quad-core ARM Cortex-A15 design with a clock speed maximum of 2.2 GHz, with a fifth A15 core that runs at a maximum of 1.0 GHz to offer better power efficiency with menial tasks.
In our testing, we are comparing the Xiaomi Mi Pad 7.9 to the Tegra 4 based Tegra Note 7, the ASUS MeMO Pad 7 based on Intel's Bay Trail Atom Z3745 SoC, the 2013 edition of the Google Nexus 7 using a Snapdragon S4 part, and when possible the Apple iPad Air with the latest A7 design.
Our browser benchmarks indicate that the Xiaomi tablet is among the fastest on the planet even in CPU limited tasks. It pulls in the fastest scores on both the Mozilla Kraken and Google Octane browser-based benchmarks, falling behind only the Apple iPad Air in the Sunspider JS test. For all four Android devices we were using the latest version of Chrome, while the iPad Air was running Safari.
We seem to have topped out on our MobileXPRT benchmark results as both the MeMO Pad 7 and the Xiaomi Mi Pad hit 299/300 points on the performance curve and nearly 100 on the user experience metric that tests UI frame rates.
The Vellamo test was recently updated to include a browser specific test in addition to multi-core efficiency test, and a "metal" test that looks at synthetic results. In all three cases, the Xiaomi Mi Pad 7.9 with the Tegra K1 takes a substantial lead, coming in at 21% faster than the Note 7 under Chrome, 26% in the multi-core testing, and 33% faster on the "metal" test that includes a graphics portion.