But each will need to do that at 60hz, so you'd still be running 2 4k screens at 60 hz.
I think that the solution is the same solution as the Pimax 4k. You're not running your Pimax at 4k but at either 1080p or 1440p which the headset samples up to 4k. I'm guessing the Pimax 8k works exactly the same. So you'd probably only need to power 2x1080p or 2x1440p. Still, I'm guessing that GTX 1080 is going to be the bare minimum spec. We'll see though, less than a week to the IFA, so I'm hoping we'll learn some more details soon.