3fps less than maximum hz

Talk about NVIDIA G-SYNC, a variable refresh rate (VRR) technology. G-SYNC eliminates stutters, tearing, and reduces input lag. List of G-SYNC Monitors.
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blaskovic
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3fps less than maximum hz

Post by blaskovic » 16 Jun 2019, 15:48

Hi everyone and sorry for my English. I have a question.

I have a monitor 144hz g-sync with v-sync on in Nvidia control panel. I read the guide and there is the advice to put -3 fps (for example on a moitor 144hz, 141 fps). I would to know if this setting only help about the lag or help also to reduce stuttering. Thank you

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jorimt
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Re: 3fps less than maximum hz

Post by jorimt » 16 Jun 2019, 16:25

If your framerate can exceed your refresh rate (144+ FPS at 144Hz), you need the -3 (minimum) FPS limit to stay in the G-SYNC range. If your framerate never exceeds your refresh rate (<144 FPS at 144Hz), the -3 FPS limit is optional.
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blaskovic
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Joined: 14 Jul 2017, 11:09

Re: 3fps less than maximum hz

Post by blaskovic » 17 Jun 2019, 10:54

jorimt wrote:If your framerate can exceed your refresh rate (144+ FPS at 144Hz), you need the -3 (minimum) .
Thank you but the option v-sync on in the Nvidia Control Panel is not enough to avoid that my fps exceed the refresh rate ? I want to understand why I have to put -3fps in this case. Thank you

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jorimt
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Re: 3fps less than maximum hz

Post by jorimt » 17 Jun 2019, 11:23

I've already answered that in my article. Read the 4th entry here for the short answer:
https://www.blurbusters.com/gsync/gsync ... ttings/15/
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Chief Blur Buster
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Re: 3fps less than maximum hz

Post by Chief Blur Buster » 19 Jun 2019, 22:33

The TL;DR version.

The differential is needed because frame rate caps are not perfect -- it's an average frame rate often, and within the cap, some frametimes are 1/143sec and some frametimes are 1/144sec and some frametimes are 1/145sec. Some of those frametimes are faster than a refresh cycle. Capping slightly below (~1fps to ~5fps below, usually 3fps) solves most of that.

Those frames that have fast frametimes can be torn or inputlagged, creating an inconsistent playfeel as your framerate transitions towards the maximum Hz (sudden latency-change effect that can throw off aiming). Capping avoids that situation.

3fps is just the common advice, though a tighter differential is doable for lower Hz (60Hz) and a slightly larger differential for higher Hz (e.g. 240Hz), but it's mostly just easiest to recommend a 3fps differential.

Now for the longer story, go see Jorim's GSYNC 101.
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