In early 2011, during a CES press event, Nvidia revealed its Project Denver CPU initiative. On Sunday evening, at another CES press conference, the company provided a glimpse of the first Denver-based processor: the Tegra K1. This next-generation SoC features dual Denver CPU cores clocked at up to 2.5GHz. The cores were designed by Nvidia, and they’re compatible with the 64-bit ARMv8 instruction set. They have a seven-way superscalar pipeline and a hefty 128KB + 64KB of L1 cache. The L1 instruction cache appears to be the larger of the two.
The Tegra K1 comes in two pin-compatible configurations. In addition to the Denver-based duallie, there’s a quad-core version based on ARM Cortex-A15 cores similar to those used in the Tegra 4. That second chip is limited to 32-bit applications, and its CPU cores will only scale up to 2.3GHz.
Based on Nvidia’s die shots, two Denver cores appear to have the same silicon footprint as four Cortex-A15s. It will be interesting to see how the two implementations compare.
At the very least, both chips should have plenty of graphics horsepower. The Tegra K1’s DirectX 11-class integrated graphics has 192 shader processors based on the Kepler microarchitecture. In Nvidia’s desktop and notebook GPUs, each Kepler SMX unit also has 192 shader processors. The low-end GeForce GT 640 includes two SMXes, while the high-end GeForce GTX 780 Ti has 15 of them.
Nvidia stopped short of revealing the graphics clock frequency, but it did show the Tegra K1 running the next-generation Unreal Engine 4. Scott was on the scene, and he describes the demo as "freaking amazing." I don’t believe that demo was running on the Denver-based variant. Nvidia did a live demo of its home-grown duallie on stage, though. The chip has only been back from the fab for a few days, according to the company.
Like its Tegra 4 predecessor, the Tegra K1 is built using 28-nm fabrication technology. Well, the Cortex-A15 version is, anyway. The official product page doesn’t list the Denver incarnation yet.