Overwatch -- Lightboost 120Hz + Fast Sync

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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by Sparky » 28 May 2017, 10:07

drmcninja wrote:
jorimt wrote:
KevOW wrote:Thank you Real and Chief for the quick response. I'm curious if any of you ran tests similar to Battle(non)sense

https://www.youtube.com/watch?v=sITJ3V_fyv4
RealNC wrote:We did G-Sync input lag tests for CS:GO. Nothing for fastsync at this point though, sorry.
No, I actually did do a Fast Sync comparison in my original input latency tests, albeit only at 144 Hz:

Image

It didn't add much latency at 144 Hz uncapped (fps_max 300 in CS:GO); this will of course vary depending on the current max refresh rate/sustained fps ratio. The last official word from Nvidia was that Fast Sync has around 8-15ms more latency than v-sync off on average:
https://www.youtube.com/watch?v=xtely2G ... t=1h34m21s

For the upcoming part #3 of my ongoing G-SYNC 101 article however, I will be comparing G-SYNC input latency against v-sync off, v-sync on, and Fast Sync across all available refresh rates, with multiple scenarios covering uncapped and varying levels of capped framerates.

Keep an eye out at the top of the below thread, along with the Blur Busters home page and social media pages for updates:
http://forums.blurbusters.com/viewtopic.php?f=5&t=3073
I'm trying to enable Fast Sync, but I'm not sure it's working. How do you enable it?

I enabled it for Overwatch.exe and Overwatch Launcher both in Nvidia Control Panel, but in-game my FPS is still showing 300. When I lowered it to 140fps with the in-game limiter, I could tell my FPS just dropped significantly, everything began to stutter and mouse movement felt different. My refresh rate is 120 so if Fast Sync was really enabled, it should've been outputting 120fps the entire time so I shouldn't have felt a difference no matter what the fps limiter was set to, no?
No, fast sync will let the game run faster than the refresh rate, and will drop the extra frames. You can tell it's working if there's no more tearing.

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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by RealNC » 28 May 2017, 11:58

When using fast sync, do NOT cap the frame rate. Fast sync only works well when your FPS is very high (300FPS and higher.)
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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by drmcninja » 28 May 2017, 18:06

RealNC wrote:When using fast sync, do NOT cap the frame rate. Fast sync only works well when your FPS is very high (300FPS and higher.)
Thank you! Now it looks better. Luckily my machine is hitting the max 300fps so Fast Sync seems to work well. Should I leave it at 300 or perhaps move it to 240? The GPU would run a little cooler at lower fps.

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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by RealNC » 28 May 2017, 21:35

drmcninja wrote:
RealNC wrote:When using fast sync, do NOT cap the frame rate. Fast sync only works well when your FPS is very high (300FPS and higher.)
Thank you! Now it looks better. Luckily my machine is hitting the max 300fps so Fast Sync seems to work well. Should I leave it at 300 or perhaps move it to 240? The GPU would run a little cooler at lower fps.
I'm not sure. Fast sync produces different results for me in different games. In some games, it caps to a multiple of the refresh rate automatically. In other games, it doesn't. And when I cap to an exact multiple (like 240FPS on 120Hz), then the game is capped to 120FPS instead.

It seems random. Not capping the frame rate, or capping it to a very high value (like 300FPS) seems to works best.

For Overwatch, I'd use vsync instead and switch the monitor to 0.008Hz above target frame rate. On 144Hz, I'd use CRU and modify the 144Hz mode to be 144.008Hz, then use the in-game limiter of Overwatch and set it to 144FPS. That produces very little input lag and gives you all the benefits of vsync.
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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by daniloberserk » 22 Aug 2017, 16:52

RealNC wrote:
drmcninja wrote:
RealNC wrote:When using fast sync, do NOT cap the frame rate. Fast sync only works well when your FPS is very high (300FPS and higher.)
Thank you! Now it looks better. Luckily my machine is hitting the max 300fps so Fast Sync seems to work well. Should I leave it at 300 or perhaps move it to 240? The GPU would run a little cooler at lower fps.
I'm not sure. Fast sync produces different results for me in different games. In some games, it caps to a multiple of the refresh rate automatically. In other games, it doesn't. And when I cap to an exact multiple (like 240FPS on 120Hz), then the game is capped to 120FPS instead.

It seems random. Not capping the frame rate, or capping it to a very high value (like 300FPS) seems to works best.

For Overwatch, I'd use vsync instead and switch the monitor to 0.008Hz above target frame rate. On 144Hz, I'd use CRU and modify the 144Hz mode to be 144.008Hz, then use the in-game limiter of Overwatch and set it to 144FPS. That produces very little input lag and gives you all the benefits of vsync.
May I ask you how can I do that? I've been trying here on my XL24020z with no success :(... I'm using and AMD GPU with the 17.7.1 driver. ToastyX 1.3.

Ty in advance!

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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by RealNC » 22 Aug 2017, 17:20

daniloberserk wrote:May I ask you how can I do that? I've been trying here on my XL24020z with no success :(... I'm using and AMD GPU with the 17.7.1 driver. ToastyX 1.3.

Ty in advance!
https://forums.guru3d.com/threads/the-t ... st-5380262

I haven't tested the OW frame limiter yet. Use RTSS and enable the frame time graph and "show own statistics" checkboxes. Set the FPS limit to 0 (disables the RTSS limiter.) Then, see if the graph line is perfectly flat when using the OW limiter. If it is, that means 144FPS on 144.008Hz will give you low latency vsync.

If the frame time is not perfectly flat, then use RTSS as the frame limiter instead. This should produce a flat graph line.
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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by daniloberserk » 22 Aug 2017, 22:07

RealNC wrote:
daniloberserk wrote:May I ask you how can I do that? I've been trying here on my XL24020z with no success :(... I'm using and AMD GPU with the 17.7.1 driver. ToastyX 1.3.

Ty in advance!
https://forums.guru3d.com/threads/the-t ... st-5380262

I haven't tested the OW frame limiter yet. Use RTSS and enable the frame time graph and "show own statistics" checkboxes. Set the FPS limit to 0 (disables the RTSS limiter.) Then, see if the graph line is perfectly flat when using the OW limiter. If it is, that means 144FPS on 144.008Hz will give you low latency vsync.

If the frame time is not perfectly flat, then use RTSS as the frame limiter instead. This should produce a flat graph line.
Thank you very much for your incredible fast reply!

So, I did this steps:

1. It seems I finally could raise my refreshrate a bit. I was trying to create a Detailed Resolution without success... But now I changed the 144Hz option on Extension Blocks. Raised to 144.008 and it seems OK. In the vsynctester.com it shows as 144.002~.

2 My RTSS doesn't had the frametime option. So I redownloaded the most recent version of rivatuner and now it seems good enough.

The frametime seems to be the same "SIM" number who appears in Overwatch (you can check the SIM number pressing Ctrl+Shift+N).

I'm really confused about all this... If you could clarify some things I'll really appreciate!

My RTSS apparently doesn't had the frametime option, so I downloaded a more recent version and could make it work.

So, I did some tests. ALL tests was made with Vsync ON/Reduce Buffering ON and Triple Buffer OFF (ingame options only).

As soon as I opened the game, it just crashed. Never saw that error before LOL
Image

So, opened again and started the tests.

RTSS OFF, INGAME LIMITER OFF:
Image

RTSS OFF, INGAME LIMITER TO 144FPS:
Image

RTSS OFF, INGAME LIMITER TO 143 FPS:
Image

RTSS TO 144 FPS, INGAME LIMITER OFF
Image

I didn't notice any tearing on the tests.

So yea, very curious for me! How accurate are this frametime readings? Because I remember seeing the article about Gsync - Input Lag on the site and on the tests it seems RTSS had more output lag then the ingame limiter: https://www.blurbusters.com/wp-content/ ... s-rtss.png

But with this tests.. RTSS on 144 FPS, Vsync ON and the refresh rate trick just made the vsync OFF and ON to have the SAME 6.9ms of output lag, which is just crazy oO..

And why ingame limiter to 143 FPS have less frametime then 144 FPS? Both without tearing.

For me, it seems a little float mouse feeling with vsync on. But probably is just placebo because I'm very used to the tearing mess/vsync off. I wish I had some gear here to test this like you guys tested the input lag on that article!

Sry for my english and ty very much for your patience!

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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by RealNC » 22 Aug 2017, 22:25

The frame time has nothing to do with input lag. 6.9ms is just 1000/144 (how long each frame stays on the screen.)

Also, I do not understand the screenshots, as they are very difficult to read and everything is transparent. And they're probably wrong. You need RTSS to see how stable the frame limiter of the game is.

Also, 144.002Hz is not good enough. 144.008Hz is safer. Otherwise, you get vsync input lag (floaty mouse.)

In the end, I recommend using RTSS@144FPS, in-game limiter off, monitor at 144.008Hz.
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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by daniloberserk » 22 Aug 2017, 22:48

RealNC wrote:The frame time has nothing to do with input lag. 6.9ms is just 1000/144 (how long each frame stays on the screen.)

Also, I do not understand the screenshots, as they are very difficult to read and everything is transparent. And they're probably wrong. You need RTSS to see how stable the frame limiter of the game is.

Also, 144.002Hz is not good enough. 144.008Hz is safer. Otherwise, you get vsync input lag (floaty mouse.)

In the end, I recommend using RTSS@144FPS, in-game limiter off, monitor at 144.008Hz.
Strange... I can read just fine every info on my browser oO. The data from RTSS is the Pink One with the big FPS on the left corner. The middle data is the Ctrl + Shift + N built in OW (where you can see the SIM numbers matching the frametime). I took pictures because everytime I used screenshots it changed the values...

The line from the left edge who's just above the SIM numbers is the frametime graph from RTSS. Almost flat with RTSS limiter and jittery with the Ingame limiter.

I used 144.008Hz in the ToastyX (144.002Hz~ is what it shows on the http://www.vsynctester.com).

Here. The infos inside the orange boxes is the only thing you probably want to know (the rest of things is netcode related).

Image

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Re: Overwatch -- Lightboost 120Hz + Fast Sync

Post by RealNC » 23 Aug 2017, 01:52

If the in-game limiter is jittery, it means it renders faster than the limit. So you'll probably get more lag with it than with RTSS.

And again: you need 144.008Hz. 144.002 is not enough. So you should raise it in CRU until you get 144.008 in the test.

Or, use the fractional FPS limit of RTSS, using the LimitDenominator setting. In that case you leave the monitor at 144Hz and use a 143.992FPS limit.
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