Trying to understand the refresh rates of VR headsets

[Youda]

So i just unpacked and setup my new HP Reverb G2, and tried it briefly in few of my games, and now comes the boring part and that is optimizing graphical settings for acceptable FPS without loosing all the image quality.

The first thing i've been wondering about, do VR headsets have something like FreeSync to handle the case when GPU is not able to deliver that much frames per second the headset is expecting? What happens, when my headset is set to 90 Hz refresh rate, but the GPU can produce only 80 FPS? Will it tear the image in half?

Second thing is about VSync. I've noticed that no matter how much i lower the details, the FPS indicator stops at 90 and never goes higher, even though the VSync in my game settings is Off. Does that mean the headset enforces VSync for itself and it will always be on?

How do i know when to stop lowering details, because GPU is already keeping up with the 90 Hz, and before i drop to the absolute bottom ugliest graphics?

[unlikely_spider]

The refresh rates are fixed at whatever settings you have in WMR, like 90 or 60. When it can't hit that rate, it has to be an even fraction of that, like 45 if you have it set to 90, or 30 if you have it at 60.

Turning on reprojection in SteamVR will add software-interpolated frames to keep it at 60 or 90 regardless of how many actual frames your system is generating at any point.

[Youda]

1 hour ago, unlikely_spider said:

The refresh rates are fixed at whatever settings you have in WMR, like 90 or 60. When it can't hit that rate, it has to be an even fraction of that, like 45 if you have it set to 90, or 30 if you have it at 60.

Turning on reprojection in SteamVR will add software-interpolated frames to keep it at 60 or 90 regardless of how many actual frames your system is generating at any point.

Hmm, ok. But what if i play DCS as standalone app outside of Steam? Is it possible to use SteamVR to play standalone DCS?

[unlikely_spider]

2 hours ago, Youda said:

Hmm, ok. But what if i play DCS as standalone app outside of Steam? Is it possible to use SteamVR to play standalone DCS?

Yes, that's what I do as well. It still uses SteamVR.