Xbox Live VP Marc Whitten broke the news on the Major Nelson podcast published today.
"This is the time where we've gone from the theory of how the hardware works…to really having them in our hands, and that's the time where you start tweaking the knobs," Whitten said.
"An example of that is we've tweaked up our clock speed on the GPU from 800MHz to 853MHz."
Overclocking is something that your average hardcore PC gamer does on a daily basis, but what does it mean for Microsoft?
For one thing it shows clearly that the company is dedicated to bringing the Xbox One's oomph as close to the PS4 as possible, so that the console war is not decided on power alone.
From what we've seen of both consoles, it seems they're already very close in power - both use AMD's Jaguar processor, after all. And no doubt this boost will bring them even further in line.
That said, each system still has its unique strengths: Sony still has a slight upper hand in terms of memory, but the Xbox One also holds an advantage in Microsoft's cloud, which can take part of the processing load off the hardware.
100 percent optimized
Whitten also revealed that the Xbox One is in internal beta within Microsoft and that developers now have access to the final dev kits.
In addition, he revealed that the Xbox One has what he called a "mono driver," a graphics driver that's "100 percent optimized" for the console.
"You sort of start with the sort of the base the DX driver and then you take out all the parts that don't look like Xbox One and you add in everything that really, really optimizes that experience," he said.
"And almost all of our content partners have really picked it up now, and it's really I think made a really nice improvement."
Like we said, each console has unique strengths, but with their raw power so close together it's clear that the upcoming console war won't be won on graphics alone.
- But are there really only two dogs in this fight? One developer thinks the iPad will be just as important as the Xbox One and PS4.
Via The Verge