The Xbox One's June SDK update gives developers access to "additional GPU resources previously reserved for Kinect and system functions," a Microsoft spokesperson told Polygon.
"For consumers," the representative said, "simply unplugging Kinect will not impact the performance of Xbox One."
Developers have the option to access that previously unavailable horsepower. Microsoft is currently working with developers to see "how they can best take advantage of these changes, and we'll have more to share in the future," the representative said.
"Yes, the additional resources allow access to up to 10 percent additional GPU performance," a company representative told Eurogamer. "We're committed to giving developers new tools and flexibility to make their Xbox One games even better by giving them the option to use the GPU reserve in whatever way is best for them and their games."
This follows last night's tweets from Xbox head Phil Spencer confirming additional GPU bandwidth will be made available. The company head did not say whether this power boost was related to Kinect in any way.
In an interview with Polygon on the day the company announced that it would make Kinect optional, Xbox executive Yusuf Mehdi said Microsoft was looking into making changes to the Xbox One's software architecture, since the console reserved some processing power for Kinect. However, that was tied to the CPU, not the GPU.
Microsoft also released the June 2014 software update for the Xbox One today, adding new features like the ability to put games and apps on an external hard drive and use real names on Xbox Live.
Correction: A previous version of this article said that the "Kinect-less Xbox One will receive a 10 percent boost in its performance due to the stripping out of the peripheral." We've updated the article throughout to account for Microsoft's statement.