News from gaming insider Pete Doss is that Microsoft is mulling significant changes to the restrictions it places on developers regarding the Xbox One's GPU. Reportedly, some 10% of total GPU horsepower is reserved for the Kinect
-- 8% for video and 2% for voice processing. Microsoft is apparently planning changes that would free up that 8% video entirely, leaving just 2% of the system's GPU dedicated to voice input.
makes this change, it could have a significant uplift on system frame rates -- and it's not clear that developers would necessarily need to patch the architecture to take advantage of the difference. Generally speaking, in the PC realm, swapping between two GPUs within the same architectural family doesn't require a driver update provided both cards were covered in the previous driver.
It's not clear how flexible the Xbox One is in this regard, but early adopters might see benefits from this change without even needing to update their software (past the patch that releases the additional resources). The reason for the shift is almost certainly the fact that the Xbox One has gotten chewed on by the PS4 over variance in frame rate. The details vary from game to game, but in the recently-released Tomb Raider (for both PS4 and Xbox One), multiple independent reports indicate that the Xbox One is running
closer to 30 FPS, while the PS4
is pushing 60 FPS.
Is 8% Enough To Matter?
Generally speaking, yes. 10% is considered the rough marker for noticeable improvements, though this can vary depending on what form the speed improvement takes. The eye is very sensitive to changes in rate-of-movement, which is why latency hitches and jerks are far more annoying than a steady slow frame rate. Most people will take a constant 30 FPS over a 40 FPS average frame rate that bounces between 20 and 60 FPS, and this sensitivity is why -- our brains evolved to notice sudden changes in motion because it's one of the best ways to avoid being something else's lunch.
But what Microsoft is also tacitly admitting with this move is that the Kinect just isn't important to people the way it wanted it to be. Giving developers the freedom to use the extra horsepower sucked down by the Kinect is a good thing for developers and gamers, but it also means that at least these first games aren't using the Xbox hardware to create the kind of alternative gaming environments Microsoft wanted.
It also may be a sign that coders are having trouble ringing full power out of the Xbox One in general. Digital Foundry recently did a test
of the 13GB Dead Rising 3 patch, with extensive performance comparisons before and after the patch was applied. Despite the developer's promises, they found no significant differences between the two in gameplay or in cut-scenes.
The gap between the GPU performance of the Xbox One
and PS4 isn't sufficient, on its own, to explain why the PS4 is pushing 60 FPS while the Xbox One can't manage much above 30 FPS. We suspect that these issues are tied to the difficulty of leveraging the Xbox One's SRAM as compared to the PS4's unified approach. Future titles should exhibit less of a gap as developers get their legs underneath them and learn the system architectures.