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PixelDuck87 wrote: ↑

27 Jul 2020, 12:07

I had no idea that's how freesync/gsync works, I always thought it would directly change the refresh rate of the monitor on the fly... Thank you for explaining this!

Yup...

"G-SYNC 101: G-SYNC vs. V-SYNC OFF w/FPS Limit":
https://blurbusters.com/gsync/gsync101- ... ettings/6/

With a fixed refresh rate display, both the refresh rate and scanout remain fixed at their maximum, regardless of framerate. With G-SYNC, the refresh rate is matched to the framerate, and while the scanout speed remains fixed, the refresh rate controls how many times the scanout is repeated per second (60 times at 60 FPS/60Hz, 45 times at 45 fps/45Hz, etc), along with the duration of the vertical blanking interval (the span between the previous and next frame scan), where G-SYNC calculates and performs all overdrive and synchronization adjustments from frame to frame.

"Refresh rate" is used interchangeably, since while VRR does adjust the refresh "rate" (how many times the scanout cycle occurs per second) it does not adjust the max "physical" refresh rate, which is what many people still primarily associate as being the "refresh rate."

To be even clearer, If you look at this video of an LCD scanout, you'll see what effectively look like top-to-bottom screen sweeps. These sweeps are individual scanout cycles. With VRR, the framerate determines how many of these sweeps occur per second, whereas the currently set physical max refresh rate determines how fast each of the individual sweeps complete:

RLCScontender wrote: ↑

27 Jul 2020, 07:20

Any form of adaptive sync/variable refresh rate adds INPUT LAG anyway.

Only relative to VSYNC OFF.

Most of the time, variable refresh rate is lower lag than any "non-VSYNC-OFF" sync technology. That's why we love it for motion-quality-priority situations. If you need to use any sync technology that is not "VSYNC OFF", then properly-overdriven (i.e. dynamic overdriven) variable refresh rate generally has the lowest possible input lag of any synchronization-enabled sync technology.

Remember, not all of us use 240Hz gaming monitors for online gaming! So we want to prioritize on motion quality while still not sacrificing much lag.

PixelDuck87 wrote: ↑

27 Jul 2020, 12:07

I had no idea that's how freesync/gsync works, I always thought it would directly change the refresh rate of the monitor on the fly... Thank you for explaining this!

There is often a ton of terminology confusion.

G-SYNC and FreeSync does change the refresh rate on the fly but not in the traditional way. The blanking interval varies in size to temporally space apart the refresh cycles. The refresh cycles still scans-out at a constant velocity (representing max Hz), as seen in high speed videos, www.blurbusters.com/scanout -- however, the interval between refresh cycles can now temporally vary. So on a 240Hz VRR monitor -- 60fps looks like perfect 60Hz, 75fps looks like perfect 75Hz, 139fps looks like perfect 139Hz. However, at all those frame rates, all the frames are scanned-out in 1/240sec (max Hz refresh rate).

So refresh speed of an individual refresh cycle is unchanged, even though the refresh rate varies (time interval between refresh cycles).

This is a big part of why 60fps on a 240Hz G-SYNC monitor is much lower lag than 60fps on 60Hz VSYNC ON -- only +4ms added VSYNC lag versus +33ms added VSYNC lag.

Turns out Rtings actually did set the monitor to 60hz for their input lag test.

So I guess there is nothing to worry about if you don't want to specifically game on fixed 60hz for some reason.
With new consoles on the way, 60hz should be a thing of the past soon anyway even for console users...

PixelDuck87 wrote: ↑

28 Jul 2020, 08:51

Turns out Rtings actually did set the monitor to 60hz for their input lag test.

So I guess there is nothing to worry about if you don't want to specifically game on fixed 60hz for some reason.
With new consoles on the way, 60hz should be a thing of the past soon anyway even for console users...

Good to know, thanks for the update!

Does this mean I should always use 280hz (regardless of fps) to achieve the lowest input lag possible?

bl00rb00ster wrote: ↑

04 Jan 2021, 05:14

Does this mean I should always use 280hz (regardless of fps) to achieve the lowest input lag possible?

In theory and practicality, yes.

Another question: How should I adjust the OD settings of my monitor? Most experiments and tables I've seen refer to the maximum refresh rate (280 hz), but what value should I choose for demanding games, like cyberpunk where my framerate (and thus hz) drops down to 60 for example? (using g-sync ofc)