Microsoft Unlocks Extra Xbox One CPU Power

Newer games have a little more CPU headroom to play with, reveals a recent leak of the Xbox One SDK.


On paper, Sony's PlayStation 4 (PS4) has a performance edge on the Xbox One from Microsoft, despite sharing a similar "Jaguar" system-on-chip (SoC) architecture from Advanced Micro Devices. A recent leak from the Xbox One's November 2014 software development kit (SDK) from hacking group H4LT revealed that game developers can now dip into the added computational resources provided by a newly unlocked processor core, potentially narrowing the gap between the rival gaming console platforms.

According to a Jan. 5 Forbes report, two of the Xbox One's eight CPU cores are reserved for the underlying operating system. Now, Microsoft is enabling developers to leverage 50 to 80 percent of one of those cores, improving performance.

The extra headroom arrives in the wake of Microsoft's decision to offer a lower-priced version of the console without the Kinect motion sensor, matching the PS4's retail price of $399.

"This connects to what we already know about the Kinect, that a certain amount of CPU power was tied up for the operations of the peripheral, and now that it's optional, that gives more leeway to developers," wrote Forbes' Paul Tassi. In June, Microsoft began offering a new base Xbox One model that did away with the Kinect controller, which was formerly issued with each and every Xbox One.

As expected, developers will have to contend with some trade-offs, particularly if their projects involve voice or gesture-based commands. "Firstly, developers need to give up custom, game-specific voice commands in order to access the seventh core at all, while Kinect's infra-red and depth functionality is also disabled," noted Eurogamer's Richard Leadbetter in his analysis of the leaked SDK.

Developers must also wrestle with some level of unpredictability introduced by users that have come to rely on the device's voice commands. Leadbetter added that "the amount of CPU time available to developers varies at any given moment—system-related voice commands ("Xbox record that", "Xbox go to friends") automatically see CPU usage for the seventh core rise to 50 per cent." In the future, Microsoft plans to issue an SDK update to help developers better schedule tasks under these conditions and deliver smoother gaming experiences.

As for the security implications of the leak, don't expect "homebrew" games to appear on the Xbox One any time soon.

"The truth is that Xbox One is just as secure now as it was before the leak," Leadbetter said. "Developers have zero access to the encryption technologies used to prevent console piracy, and while the documentation includes instructions on how to turn retail consoles into development hardware, the process doesn't work without server-side authentication, which homebrew enthusiasts are unlikely to get from Microsoft."

Budding game developers may glean something from the SDK, but their creations must still be Microsoft-approved. "In short, while the SDK will allow developers to write code and compile it, they will have no target hardware to run it on without a comprehensive hack of the Xbox One console itself," concluded Leadbetter.

Pedro Hernandez

Pedro Hernandez

Pedro Hernandez is a contributor to eWEEK and the IT Business Edge Network, the network for technology professionals. Previously, he served as a managing editor for the network of...