Microsoft director of product planning Albert Penello has spoken out to dispel an enduring rumor about the Xbox One. It's been suggested that the Xbox One features a second secret graphics processing unit (GPU) hidden somewhere in the system, but this is not true, Penello says.

"I thought I had already said something about that. There is no 2nd GPU, there is no stacked GPU," Penello said on Twitter. Later writing on Reddit, Penello noted that Microsoft's recent Direct X12 announcement might have made the rumor re-appear.

"I didn't think [the second GPU rumor] was festering because I thought I'd already commented on it. For some reason the DX12 announce seemed to make it resurface," he said.

Regarding DX12 specifically, Penello said he's not that completely caught up on the new graphics API just yet, and so he's not sure how it will directly impact Xbox One. Still, he said players can expect advancements to performance over time on Xbox One.

"I know we're continually improving our tools for developers, as we did with Xbox 360, so you'll see consistent performance improvements over time," he said.

Last week, Microsoft said gamers can expect more Xbox One titles to run in 1080p over time as studios discover and improve upon development techniques.