Vsync - nVcpl vs DCS in-game - heads up! feat. Frame times and stuttering

[Bucic]

It's been a while since I've seen such an insidious smoothness killer. I advise anyone to test this, regardless whether you run G-Sync or not. RCtrl+Pause may be enough to see the difference, you can use CapFrameX if you're really suspiscious about this piece of advice.

So, here's the story. I'm a fresh G-Sync adept and I've been looking through several G-Sync infored guides. Many of them advise G-Sync+Vsync setup. The caveat is, some guides and commenters point out you should use Vsync On in nVCpl (nVidia Control Panel) and disable the in-game Vsync. So I did that. What a frametime increase! Everything started moving choppy...(ly?). I went back to the old G-Sync+VsyncINGAME setup immediately.

 

TLDR:

Use in-game V-sync (as of spring 2024 I also use in-DCS FPS limit of 60)

in nVidia: Use 3D application setting

 

To investigate:

FPS limit: nVcpl vs in-DCS

 

 

Edited October 4, 2024 by Bucic

[SharpeXB]

I think you can run G-Sync with Vsync off altogether. Vsync can add latency and all it will do with G-Sync is act as a frame rate limiter. It’s unlikely that DCS will run in excess of a high refresh rate monitor but you can also just cap your frame rate in NCP to match your display. 

[Bucic]

7 hours ago, SharpeXB said:

I think you can run G-Sync with Vsync off altogether. Vsync can add latency and all it will do with G-Sync is act as a frame rate limiter. It’s unlikely that DCS will run in excess of a high refresh rate monitor but you can also just cap your frame rate in NCP to match your display. 

Quote

G-SYNC + V-SYNC “On”:
This is how G-SYNC was originally intended to function

https://blurbusters.com/gsync/gsync101-input-lag-tests-and-settings/2/

full guide - G-SYNC 101: Optimal G-SYNC Settings & Conclusion | Blur Busters - https://blurbusters.com/gsync/gsync101-input-lag-tests-and-settings/14/

Edited September 26, 2023 by Bucic

[SharpeXB]

3 hours ago, Bucic said:

https://blurbusters.com/gsync/gsync101-input-lag-tests-and-settings/2/

full guide - G-SYNC 101: Optimal G-SYNC Settings & Conclusion | Blur Busters - https://blurbusters.com/gsync/gsync101-input-lag-tests-and-settings/14/

 

Aha. Good info. I was trying to find that again to look into this. 

[SharpeXB]

I tried messing around with this again. For me definitely Vsync should be Off. Wow. I capped the frame rate in NCP at 118 on a 120Hz display and set everything else in NCP to default. Low Latency to and Triple Buffering to default Off. Wow is that smooth. 

[Bucic]

to do dump:

Limit FPS to refresh rate minus 2

Windows Defender exclusion?

https://forum.dcs.world/topic/344067-dcs-update-discussion-february-2024/?do=findComment&comment=5391411

GPU Hardware Scheduling in BIOS?

check GPU RAM usage + vs 4k liveries

affinity exclude CPU0 ?!

 

 

[SharpeXB]

8 minutes ago, Bucic said:

to do dump:

Limit FPS to refresh rate minus 2

Windows Defender exclusion?

https://forum.dcs.world/topic/344067-dcs-update-discussion-february-2024/?do=findComment&comment=5391411

GPU Hardware Scheduling in BIOS?

check GPU RAM usage + vs 4k liveries

affinity exclude CPU0 ?!

 

 

Other than the first step with the frame rate limit I’ve never touched those other things. Nor do I really know what they are. Everything works really well though so I’ll leave it alone. 

[Bucic]

4 minutes ago, SharpeXB said:

Other than the first step with the frame rate limit I’ve never touched those other things. Nor do I really know what they are. Everything works really well though so I’ll leave it alone. 

I don't tweak for the sake of it anymore. The problem is it's not smooth on my system, even by capping FPS from some 150 to 60. And it seems it's the dreaded "low frametimes, still choppy" case. Especially with The Channel Map cities. I haven't tested it on other maps yet.

I've got LG UltraGear 27GP850P Gsync monitor.

 

 

[LucShep]

You can also try Scanline Sync (aka S-Sync), as alternative method. Just follow the linked tutorial.

It's pretty much using V-Sync OFF without the screen tearing. 
You can also use "Fast Sync" (instead of "Force OFF") in conjunction to it - works even better that way in DCS, in my experience.
Also works fine with head-tracking.

Matter of preferences but, at least with 60Hz refresh-rate, I prefer it to GSync or FreeSync.
It's really smooth, and as close as it gets to V-Sync ON without its performance and latency penalties.

The major downside of Scanline Sync is that you really need to ensure the GPU does not work at over 90% of usage, otherwise it gets very choppy real fast.

 

EDIT - added video about someone disserting about it:

Edited March 6, 2024 by LucShep

[Red_Pilot]

Thanks for that info.. But I can't edit RTSS fils in profiles folder. Because of something like 'contact the owner of the file' when I try to save changes 

[LucShep]

On 3/9/2024 at 2:43 PM, Red_Pilot said:

Thanks for that info.. But I can't edit RTSS fils in profiles folder. Because of something like 'contact the owner of the file' when I try to save changes 

If you mention manually ediiting the .CFG files in the profile folder, you may need Notepad++ in "administrator mode".

Or, alternatively, you can simply take those files (ones you want to edit) out of there, edit them and, once you're done, put them back again.
Copy/paste them into another folder (a new folder in the desktop, for example) and, after editing them, copy/paste them back again.

Edited March 10, 2024 by LucShep

[LucShep]

Just a FYI, newest version of RTSS makes setting up Scanline Sync a little easier to do.
Now you just have to set the correct negative value (to hide the tear line) for the Scanline Sync to activate, put V-Sync OFF in game (or force it "OFF" in the driver settings) and off you go.

Calculation formula for that Scanline Sync value ---> "Sync total" - "Sync Line 0" = "Scanline Sync value"

Example, for 3840 x 2160 resolution (4K) the Sync total for this resolution is 2250.
In my experience, for most games running in 4K, the tear line disappears with the Sync line 0 set to 2110.

2250 - 2110 = 140

Therefore, for 4K resolution, I type in "-140" in RTSS's box dedicated to Scanline sync.
For 1080P resolution, "-50" in RTSS's box dedicated to Scanline sync seems to work fine.

Bigger or smaller negative number will adjust position of the tear line, higher or lower in the screen (objective is to get it where it can't be seen, usually at the very bottom). 
Important: you must use negative numbers.

Edited March 23, 2024 by LucShep