Is this placebo?

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RyuKobs
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Joined: 11 Nov 2019, 13:55

Is this placebo?

Post by RyuKobs » 11 Nov 2019, 14:07

Hey guys!

I am new to the forums sorry if I posted this in the wrong section.

I replayed GTA San Andreas few days ago, the game is capped at 30 fps, I played it at 60hz refresh rate and I got a bit nauseous I then switched to 120hz and I was able to play the game without getting sick. Is this supposed to happen I mean framerate is capped at 30fps It should not matter what refresh rate I play right :S

Sparky
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Joined: 15 Jan 2014, 02:29

Re: Is this placebo?

Post by Sparky » 11 Nov 2019, 18:34

In theory, it shouldn't matter, but that 30fps cap might not actually be exactly 30fps, so you can get the 33ms of animation happening in 16.7ms of on-monitor time, and then the next frame you have 33ms of animation happening in 50ms.

That's assuming v-sync on. With v-sync off, it gets more complicated, and depends on how you count.

At the higher refresh rate, instead of 33ms of animation happening in 16.7 or 50ms, it would happen in ~25 or ~42ms. If you have v-sync off, you'll get tearing once every four refreshes instead of every other refresh.

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RealNC
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Re: Is this placebo?

Post by RealNC » 21 Nov 2019, 18:11

It's not placebo. It's called judder due to the 30FPS cap not being synced to the monitor. As Sparky said, judder is less noticeable at higher Hz.

However, if you want to completely get rid of it, you should use 120Hz with 1/4 vsync in nvidia inspector. This will sync the game's output to 1/4 of your Hz (120/4 = 30.) There's been some bugs in the nvidia driver though the last couple of years where 1/x vsync sometimes doesn't work, or requires a reboot.

The best solution to this problem though is to have a VRR monitor (g-sync, or an LFC capable freesync display) and play at the highest Hz the monitor supports.
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