A story posted over at UploadVR has some interesting information that came out of the final days of GDC last week. We know that Valve, HTC and Oculus have recommended users have a Radeon R9 290 or GTX 970 GPU or higher to run virtual reality content on both the Vive and the Rift, and that comes with a high cost for users that weren't already invested in PC gaming. Valve’s Alex Vlachos has other plans that might enable graphics cards from as far back as 2012 to work in Valve's VR ecosystem.
Valve wants to lower the requirements for VR
Obviously there are some trade offs to consider. The reason GPUs have such high requirements for the Rift and Vive is their need to run at 90 FPS / 90 Hz without dropping frames to create a smooth and effective immersion. Deviance from that means the potential for motion sickness and poor VR experiences in general.
From UploadVR's story:
“As long as the GPU can hit 45 HZ we want for people to be able to run VR,” Vlachos told UploadVR after the talk. “We’ve said the recommended spec is a 970, same as Oculus, but we do want lesser GPUs to work. We’re trying to reduce the cost [of VR].”
It's interesting that Valve would be talking about a 45 FPS target now, implying there would be some kind of frame doubling or frame interpolation to get back to the 90 FPS mark that the company believes is required for a good VR experience.
Image source: UploadVR
Vlachos also mentioned some other avenues that Valve could expand on to help improve performance. One of them is "adaptive quality", a feature we first saw discussed with the release of the Valve SteamVR Performance Test. This would allow the game to lower the image quality dynamically (texture detail, draw distance, etc.) based on hardware performance but might also include something called fixed foveated rendering. With FFR only the center of the image is rendered at maximum detail while the surrounding image runs at lower quality; the theory being that you are only focused on the center of the screen anyway and human vision blurs the periphery already. This is similar to NVIDIA's multi-res shading technology that is integrated into UE4 already, so I'm curious to see how this one might shape out.
Another quote from UploadVR:
“I can run Aperture [a graphically rich Valve-built VR experience] on a 680 without dropping frames at a lower quality, and, for me, that’s enough of a proof of concept,” Vlachos said.
I have always said that neither Valve nor Oculus are going to lock out older hardware, but that they wouldn't directly support it. That a Valve developer can run its performance test (with adaptive quality) on a GTX 680 is a good sign.
The Valve SteamVR Performance Test
But the point is also made by Vlachos that "most art we’re seeing in VR isn’t as dense" as other PC titles is a bit worrisome. We WANT VR games to improve to the same image quality and realism levels that we see in modern PC titles and not depend solely on artistic angles to get to the necessary performance levels for high quality virtual reality. Yes, the entry price today for PC-based VR is going to be steep, but I think "console-ifying" the platform will do a disservice in the long run.