Nvidia unveiled the next-generation version of its Tegra system-on-a-chip tonight at its CES press conference. The new Tegra K1 has two important selling points. The first is that it uses a GPU with 192 CUDA cores based on Nvidia's Kepler GPU architecture, the same used in the desktop GeForce GT 600- and 700-series GPUs. Secondly, some versions of the chip will be the first to ship with Nvidia's custom "Denver" ARM CPU, a 64-bit architecture that supports the ARMv8 instruction set.
Combining its desktop and mobile GPU architectures has been on Nvidia's roadmap for some time now, as we saw at the company's GPU Technology Conference in March of 2013. The difference is that now we have some idea of just how powerful that GPU will be: at 192 CUDA cores, the Tegra K1 has roughly the same raw processing horsepower as a GeForce GT 630 or 635, a low-end dedicated GPU from early last year. Memory bandwidth and throttling will also affect performance, but this gives us a decent idea of where Tegra K1 is relative to Nvidia's desktop cards.
Nvidia CEO Jen-Hsun Huang spent a fair chunk of time talking about the benefits of using the same GPU architecture across both PCs and mobile devices. Since the Tegra K1 supports the same API levels and hardware features as a full GeForce GPU, game and middleware developers will theoretically have an easier time porting their engines from desktops and game consoles to phones and tablets. Nvidia's current Tegra GPUs don't support newer APIs like OpenGL ES 3.0, so support for the full version of OpenGL 4.4 is a nice leap forward.
The CPU gets more complicated. There will be two different, pin-compatible versions of the Tegra K1 that are differentiated by their CPUs. One will use four ARM Cortex A15 cores (plus one power-saving "shadow" core) running at up to 2.3GHz. That's not much different from the CPU configuration used in the current Tegra 4. Only the higher-end version will use the new 64-bit Denver architecture, in a dual-core configuration running at up to 2.5GHz.
Other details about the chip, including the manufacturing process, weren't discussed. In one slide comparing the K1's performance to that of the Xbox 360 and PlayStation 3, Huang noted that the Tegra K1 used just five watts of power, but it's not clear under what conditions we can expect that kind of power draw.
The Tegra K1 is the latest ARM CPU architecture to go 64-bit, but it's not the first: Apple's 64-bit A7 is already shipping in the latest iPhones and iPads, and Qualcomm will be bringing the 64-bit ARM Cortex A53 architecture to market in the mid-range Snapdragon 410. In the server room, AMD plans to bring its first ARM-based Opteron chips to market this year, which will be based on the 64-bit Cortex A57 architecture. 2014 is poised to be the year when 64-bit goes mainstream in ARM devices.
Huang didn't mention when either version of K1 would be available in shipping devices, but AnandTech reports that the A15 version will ship in the first half of this year, and the Denver version will ship in the second half. It's a fair bet that we'll learn more at this year's GPU Technology Conference in March.
