The Xbox One X is set to be a powerful machine. Microsoft’s latest console, set to launch in November for $499, promises 4K resolution gaming at an ultra-fast 60 frames per second. But an interview published Saturday suggests not all is rosy on this front. The development team behind Killing Floor 2, a first-person shooter released last year, has confirmed that the game will not run at full 4K, as this would have meant a drop in frame rate.

Speaking to WCCF Tech, Dave Elder, senior graphics programmer on Killing Floor 2, said:

Killing Floor 2 runs at native 1800p, fixed resolution (no checkerboarding) on Xbox One X. We did experiment with true 4k rendering, but the frame rate drop was a bit too significant. 1800p provides the optimal balance between visual quality and performance in Killing Floor 2.

We don’t have a specific frame rate target for XBox One X, although the game does run at higher frame rates than the base Xbox One, even at 1800p resolution. We will be using Ultra textures on Xbox One X. We are also increasing the resolution of our shadow maps and shadow draw distance.

Watch a trailer for Killing Floor 2 below.

This could be an issue for Microsoft, which hopes to distinguish its console from the lower-performance PlayStation 4 Pro. Both consoles promise to play the same games as the Xbox One and PS4 respectively, but at 4K resolution. Where the PS4 Pro offers graphics performance of 4.2 teraflops, the Xbox One X offers six teraflops. That means that while Sony’s console may use graphical tricks like checkerboarding to make the game seem like it’s running at 4K, Microsoft promises its games will run at true 4K.

If Killing Floor 2 can’t reach native 4K at 60 frames per second, it undermines one of the reasons why someone would choose to buy an Xbox One X. The PS4 Pro version will also offer Ultra-level textures and 1800p resolution but uses the aforementioned checkerboarding trick to render. The PS4 Pro is $100 cheaper, but if they both offer similar experiences, it may be hard to justify the extra cost.

It’s not all bad news, though. Elder confirmed that development for the One X is a breeze, and the upgrades only took around four hours to develop. With that in mind, it bodes well that many developers will choose to utilize the added power of the One X to the best of their ability.

Photos via Microsoft