One thing to consider: Right now people with Vives tend to apply way more supersampling than they should. Many run games with a lot of reprojection going on.
I got a Titan X Pascal running at 2+ Ghz and with Supersampling at 1.6 I occationally run into reprojection in games like The Gallery: Episode 2 or Dead Effect 2.
Will it be able to power the Pimax. I am sure it will.
I keep reading about people gaming with 1070's claiming to run at 2.0 supersampling. Yes that works but not at 90hz and with loads of reprojecting going on. I don't like it because the hands/guns are jittery when reprojecting even if the rest is fluid.
We do not know how brainwarp will work. It could be jarring whenever the pimax drops a frame. So far we only saw fruit ninja and the blue. Those games should never drop a frame obviously.
I don't wanna spread doom and gloom but I am sure the message "anything that runs VR now" is not the right answer.
It's at least more like "Anything that runs VR with a Supersampling Value at 1440p without reprojection". There are not many GPUs left once you apply that rule. My guess is anything 1070 upwards and we might have to lower some details in some games along the way too. I am 100% sure it will be totally worth it though!