The Nintendo Switch—the hybrid portable games console/tablet due for release in March 2017—will be powered by Nvidia's older Tegra X1 SoC and not its upcoming Tegra X2 "Parker" SoC as initially rumoured.

The use of Tegra X1, which also powers the Nvidia Shield Android TV, means the graphics hardware inside the Switch is based on Nvidia's older second-generation Maxwell architecture, rather than the latest Pascal architecture. While the two architectures share a very similar design, the Switch will miss out on some of the smaller performance improvements made in Pascal. It's not yet known whether the hardware in the Switch will be manufactured on the more power efficient 16nm process (as used by Pascal) or whether it will remain at 20nm.

That the Switch uses an older architecture may come as a disappointment to those hoping for Xbox One or PlayStation 4 power in a portable. But more telling than the SoC itself is the clock speed it runs at. Multiple sources have confirmed to Digital Foundry that the Switch will run its GPU at two different clock speeds, depending on whether it's docked or whether it's being used as a portable—and the difference between the two is huge.

When docked, the Switch's GPU runs at a 768MHz, already lower than the 1GHz of the Shield Android TV. When used as a portable, the Switch downclocks the GPU to 307.2MHz—just 40 percent of the clock speed when docked. Even more startling is that Nintendo is giving developers the option of ignoring the higher GPU clock speed entirely, running it at the lower clock speed even when docked. According the documents received by Digital Foundry, this is "the final specification for the combinations of performance configurations and performance modes that applications will be able to use at launch."

Nintendo Switch Specs (as confirmed by Digital Foundry) CPU: Four ARM Cortex A57 cores (theoretical max 2GHz)

GPU: 256 CUDA cores (theoretical max 1GHz)

Architecture: Nvidia second-generation Maxwell

Texture: 16 pixels/cycle

Fill: 14.4 pixels/cycle

Memory: 4GB

Memory Bandwidth: 25.6GB/s

VRAM: Shared

Storage: 32GB, max transfer rate 400MB/s

USB: USB 2.0/3.0

Video Output: 1080p60

Display: 6.2-inch IPS LCD, 1280x720 pixels, 10-point multi-touch support

Given the Switch is highly likely to use a 720p screen rather than 1080p—this is currently assumed to be a 6.2-inch IPS LCD with 10-point multi-touch support—there is some overhead to run games at 1080p when docked. However, it's questionable how many developers will go to the effort of creating games that make use of the extra horsepower when docked, rather than simply opting to program for the slower overall GPU clock speed.

While GPU performance is variable, the rest of the Switch's specs remain static. Its four ARM A57 CPU cores are purported to run at 1020MHz regardless of whether the console is docked or undocked, while the memory controller can run at either 1600MHz or 1331MHz in either mode.

These specs certainly won't challenge the pixel-pushing performance of an Xbox One or a PS4, and it raises yet more questions about how much third-party support will come to Switch. Older games like Skyrim—as shown in the reveal trailer—may appear on Switch, but cutting edge games may take longer to arrive, if they do at all.

Despite the performance deficiencies compared to the competition, the Switch still represents a sizeable jump in performance over the Wii U. That's not to mention the performance impact of any of the as-yet-unknown architectural tweaks Nintendo and Nvidia will have made to the Switch hardware. Nintendo is, once again, doing something very different with its console, choosing to ignore the high-end hardware of its competitors in favour of a console with potentially far more mainstream appeal.

With just over three months to go until the launch of the Switch and plenty of unknowns remaining, expect to hear a lot more about the console in the coming weeks. Nintendo is holding a press conference in Tokyo on January 13, with regional events taking place at the same time. Ars will be in attendance and will bring you a full hands-on.