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Thank you

flaviowolff wrote: ↑

03 May 2020, 00:14

Thank you

You're welcome.

janos666 wrote: ↑

12 Feb 2020, 09:03

What I am wondering about if it's normal to have tearing with a low fps cap and G-Sync without V-Sync.

Off the topic but since I wish to refer back to this... I managed to get FreeSync working on the LG C9 and a Ryzen+Vega notebook. It behaves the same as G-Sync Compatible: occasional and small but perceivable tearing near the bottom of the screen with fairly high fps caps (say 110-117 for 120Hz with a 40-120 range). Similarly, I have to go pretty low with the cap (like <90 or so) to eliminate it (may be still not entirely but good enough not to be noticeable even when I am concentrating on it). At least now I know this won't change with nVidia driver updates (same goes for the slight flickering of dark shades on frame-time spikes).

janos666 wrote: ↑

08 May 2020, 17:45

janos666 wrote: ↑

12 Feb 2020, 09:03

What I am wondering about if it's normal to have tearing with a low fps cap and G-Sync without V-Sync.

Off the topic but since I wish to refer back to this... I managed to get FreeSync working on the LG C9 and a Ryzen+Vega notebook. It behaves the same as G-Sync Compatible: occasional and small but perceivable tearing near the bottom of the screen with fairly high fps caps (say 110-117 for 120Hz with a 40-120 range). Similarly, I have to go pretty low with the cap (like <90 or so) to eliminate it (may be still not entirely but good enough not to be noticeable even when I am concentrating on it). At least now I know this won't change with nVidia driver updates (same goes for the slight flickering of dark shades on frame-time spikes).

Yeah, again, it's very possible that without the module, G-SYNC operation is more prone to drift with G-SYNC on + V-SYNC off within it's working range, resulting in more bottom-screen tearing at lower framerates than its hardware counterpart.

That said, again, it has been established that G-SYNC on + V-SYNC on eliminates all tearing within its range without adding further (single, complete frame delivery) input lag, be it G-SYNC or G-SYNC Compatible, so it's a (probably unavoidable) fringe issue.

<anecdotal>
May very well be repeating myself (feel free to ignore this part), but G-SYNC was always intended to be used with the V-SYNC option, it just wasn't called that, and it wasn't an option at first; original G-SYNC was G-SYNC + the V-SYNC option (both are part of a whole). It only reverts to standard V-SYNC behavior when your framerate exceeds the refresh rate FYI, and isn't V-SYNC within the refresh rate with G-SYNC active, but a component of G-SYNC that strictly adheres to the VBLANK to prevent all possible tearing.

Both standalone V-SYNC and G-SYNC + the V-SYNC option adhere to the VBLANK, obviously, but G-SYNC + V-SYNC doesn't incur any extra input lag (as standalone V-SYNC does), since the display is now slave to the GPU. The only reason V-SYNC adds input lag, is it makes the GPU wait, whereas G-SYNC + V-SYNC (within the refresh rate) doesn't.

Further, your literal input lag reduction with G-SYNC on + V-SYNC off over G-SYNC on + V-SYNC on within the refresh rate is the tearing seen, nothing more.

Further explanation for anyone interested can be read in entry #2 here:
https://blurbusters.com/gsync/gsync101- ... ttings/15/
</anecdotal>

It's not that I try to be against GSync+Vsync on principle. I simply like experimenting and this tearing thing seemed a little weird at first (compared my paper shaped expectations). I am much more concerned about the flickering of dark shades near the low end of the range, so the tearing test was only a bonus after I had FreeSync set up to check that (I was curious if LFC might work differently or G-Sync Compatible and FreeSync are somewhat different modes on the TV since one is theoretically HDMI VRR and the other is 'unknown' at this point: may be HDMI VRR support is already in the AMD driver unadvertised or may be LG supports the old proprietary HDMI FreeSync version now).

janos666 wrote: ↑

08 May 2020, 19:08

It's not that I try to be against GSync+Vsync on principle. I simply like experimenting and this tearing thing seemed a little weird at first (compared my paper shaped expectations).

Yeah, compulsive reflex on my part, not necessarily directed at the core of your comment; just a lot of people are the least clear on the whole VRR/V-SYNC option subject, and I'm used to having to blurt that out (or something like it) any time it is brought up.

That, and I have nothing against anyone running G-SYNC on + V-SYNC off, to be clear. It's simply going to tear at points is all.

janos666 wrote: ↑

08 May 2020, 19:08

I am much more concerned about the flickering of dark shades near the low end of the range, so the tearing test was only a bonus after I had FreeSync set up to check that (I was curious if LFC might work differently or G-Sync Compatible and FreeSync are somewhat different modes on the TV since one is theoretically HDMI VRR and the other is 'unknown' at this point: may be HDMI VRR support is already in the AMD driver unadvertised or may be LG supports the old proprietary HDMI FreeSync version now).

Flicker is expected at lower framerates with VRR, but it's usually only noticeable on loading screens at very low VRR "refresh" rates. It can also be a sign of partial or complete incompatibility with the display it is running on, but in that case it would be considered longer durations of complete blanking, and on an official G-SYNC Compatible display, this is unlikely.

As for OLED, it does rely on forms of dithering in the darker shades, so it's interaction with VRR in certain circumstances could be a factor.

Yes, it's not fullscreen total blanking kind of flicker (I know what that looks like, it happened in HDR when I force-enabled G-Sync with early beta VGA driver and pre-Gsync public TV firmware).

It's a slight shift in the tone response (~gamma) on near-black shades. A similar thing is observed when I turn G-Sync on/off (and look at test patterns or use a color sensor). That's why I wasn't sure LFC worked as expected with G-Sync Compatible or the TV dropped out of G-Sync mode with high frametimes (I am not sure that's how it works but this loading screen flickering and manual G-Sync on/off gamma drift together pointed to that direction).

Indeed, it's possible LG now uses some kind of temporal dithering (the panel runs at 240Hz since 2019 but only 120Hz is allowed for anything, internal motion interpolation included) and VRR might interferes with that. But I don't see any sings of that kind of dither noise (although it would be hard to spot with 240Hz). Some static dither is clearly used though (heavily on near-black). And then there was the "chroma overshoot" issue in 2018 (a very bad description but let's stick to the original name) which also affected dark gray shades only, so may be that's "bleeding back" with VRR and high frametimes (it was never solved at basic hardware level, only mitigated for the most part with software tricks like tweaked dithering).

After I tested FreeSync's LFC behavior I realized it's also trivial to test (and nor compare) G-Sync's sub-range behavior by setting a low fps cap (for example, 35fps cap would result in 30 effective fps with regular Vsync and not measure as 35 while there is no tearing or crazy judder).

janos666 wrote: ↑

09 May 2020, 14:15

It's a slight shift in the tone response (~gamma) on near-black shades. A similar thing is observed when I turn G-Sync on/off (and look at test patterns or use a color sensor). That's why I wasn't sure LFC worked as expected with G-Sync Compatible or the TV dropped out of G-Sync mode with high frametimes (I am not sure that's how it works but this loading screen flickering and manual G-Sync on/off gamma drift together pointed to that direction).

Yes, it would be difficult not to conflate these when trying to isolate for testing in this instance on this panel type.

janos666 wrote: ↑

09 May 2020, 14:15

Indeed, it's possible LG now uses some kind of temporal dithering (the panel runs at 240Hz since 2019 but only 120Hz is allowed for anything, internal motion interpolation included) and VRR might interferes with that. But I don't see any sings of that kind of dither noise (although it would be hard to spot with 240Hz). Some static dither is clearly used though (heavily on near-black). And then there was the "chroma overshoot" issue in 2018 (a very bad description but let's stick to the original name) which also affected dark gray shades only, so may be that's "bleeding back" with VRR and high frametimes (it was never solved at basic hardware level, only mitigated for the most part with software tricks like tweaked dithering).

I only own a 2017 LG C7 (which I don't actually use for gaming), but yes, I do keep up-to-date on OLED, and was aware of the overshoot issue on the 2018 models; part of why I mentioned dithering possibly being a factor during VRR operation.

Not something I've tested or observed myself though, so I can't provide much more input than that at this juncture.

so i play apex legends on a 75hz freesync monitor with a gtx 1070. right now i have G SYNC on in NVC, ALL V sync off (NVC and In game), and i cap my fps with riva tuner at 72 fps. is that good? whats the way to have smoothest snappiest experience?

kofman13 wrote: ↑

23 May 2020, 14:42

so i play apex legends on a 75hz freesync monitor with a gtx 1070. right now i have G SYNC on in NVC, ALL V sync off (NVC and In game), and i cap my fps with riva tuner at 72 fps. is that good? whats the way to have smoothest snappiest experience?

Optimal G-SYNC settings are here for repeat reference:
https://blurbusters.com/gsync/gsync101- ... ttings/14/