EVERYBODY - READ THIS *** VSYNC *** (UPDATED)

[bluefang]

edit: I made a mistake. Need to look/think more closely. But your first entry cant be right.

I just retested the first use-case, with monitor Fixed, Nvidia vsync off and condor v-sync on and indeed get ~150 fps (though it is highly variable). I can't explain it.

But what I dont understand is that you never get more than 60 FPS with g-sync. I assume your monitor is capable of more than 60? Most (non sim) gamers buy g-sync monitors to get 144-200+ FPS/Hz without screen tearing. Are you sure G sync was enabled in nvidia control panel?

Yes - I my monitor has a max refresh rate of 144Hz - so I can't explain why when G-sync is on, Condor caps out at ~60fps - and yes, I was using the setting in the Nvidia Control Panel app that enables / disables G-Sync.

When I have G-Sync on and just displaying the Windows desktop, with no 3D apps running, my monitor says the current refresh is 60Hz. Maybe Windows / Nvidia driver has a default refresh rate of 60Hz. I really don't understand.

So disabling G-Sync is not an option.

I dont follow. Why not? I mean, it wouldnt be my first choice, but when the monitor runs at a fixed 60Hz instead of G Sync, according to your table, you can get basically get anything you want from 150+ FPS or 60FPS synced as OXO suggests, (or 24 fps if for some reason you prefer that ).

I think what I meant to say was that enabling V-sync in the Condor settings is not an option. As it seems, whenever I do that, the FPS drops down to ~24fps, no matter what the other settings are set to - which I find unusable).

Without G-Sync enabled, I can get 150+ FPS, but it doesn't look good - it actually feels choppy - and there is some tearing during large movements in Condor.

I am perfectly fine running with G-Sync always enabled and the smooth 60fps I am getting with that setting - but would be interested to see the results from anyone else that has a G-Sync monitor.

[p_a_harvey]

I went ahead an made a table of the 3 relevant settings and the results produced by each setting... This was tested on my own landscape as well as Slovenia - with Slovenia producing slightly lower fps when both v-sync settings are off.

condor-3-vsync-table.png

It looks like, regardless of the Nvidia setting for the G-Sync Enabled or Disabled, if I have V-sync enabled in Condor, then the FPS drops down to the really low point (~24fps). So disabling G-Sync is not an option.

Really nice table!

But did you use "Fullscreen" mode or did you use "Fullscreen emulation"? I don't have a G-Sync monitor, but I get 24fps when V-Sync is enabled with "Fullscreen" mode, but I get 60fps when using "Fullscreen emulation".

I believe that the low frame rate in "Fullscreen" mode was an issue from back in Condor 2 (there was a workaround in the forums that involved modifying the Setup.ini file and changing the values of Numerator and Denominator). The simpler workaround is to use "Fullscreen emulation".

[janjansen]

[]

Im not convinced you actually have G-sync working at all. Maybe grab the nvidia g-sync pendulum demo from here:
https://www.nvidia.com/en-us/geforce/community/demos/

And lets see if it works with that as expected. You definitely should be able to get ~144 FPS and with no tearing.

[janjansen]

I found I actually still have a variable refresh rate monitor (freesync rather than g-sync, so its not certified, but nvidia lets me enable VRR) so I can do some testing.

First off, I want to emphasize, I have not yet been able to reproduce the problems OXO is referring to, so I have no way of knowing for sure if the G-sync settings Im trying, do solve that problem or not. Try at your own risk!

After enabling G-sync for my monitor in nvidia control panel, nothing changed for me at all, until I also changed the "monitor Technology" setting from fixed refresh to G-sync compatible. You can do this either in the global setting (assuming you dont override it in the program settings), or program setting for condor 3.

Once I did that, G-sync appears to work, and I dont seem to be getting any tearing in high or low FPS conditions, though its hard to say for sure without much more extensive testing since my monitor has a fairly limited refresh rate range.

Despite g-sync being enabled, with condor vsync disabled, frame rate is unconstrained, and I can get >300FPS, which presumably could still trigger the very problem we are trying to avoid, unless maybe if you have one of these crazy 400+Hz monitors. So enabling G-sync alone is probably NOT good enough.

If I enable V-sync in condor with G-sync active, and vsync for condor in nvidia control panel set to "application", FPS is constrained to the max 75Hz of my monitor. So unlike other posters, Im not getting 20 or 24FPS. It seems to work just fine. Im quite sure this combination, if it works for others, will solve the tow rope problem, Im much less sure Im actually getting any benefit from G-sync at lower FPS, my monitor has no way of showing refresh rate, so I dont know for sure if it varies.

The last setting I tried , is the "max frame rate" setting in nvidia settings. This limits the frame rate even if condor v-sync is off and without interfering with g-sync. I read elsewhere (unrelated to condor) that the recommended setting for this in combination with g-sync, is the maximum refreshrate of your monitor minus 3. Dont ask me why, maybe something with triple buffering, I have no idea. But this combination of settings I think will let you get all the benefit of g-sync, and hopefully, presumably, none of the problems of disabling v-sync in condor as FPS will never be higher than your monitor refresh rate. Again though, this is conjecture, I cant vouch you wont get the tow rope or sink issue with these settings, but I would be very surprised.

Nota bene; every time you change anything in nvidia control panel, you need to fully exit condor and restart it to take effect. Just hitting refly isnt enough.

[bluefang]

I went ahead an made a table of the 3 relevant settings and the results produced by each setting... This was tested on my own landscape as well as Slovenia - with Slovenia producing slightly lower fps when both v-sync settings are off.

condor-3-vsync-table.png

It looks like, regardless of the Nvidia setting for the G-Sync Enabled or Disabled, if I have V-sync enabled in Condor, then the FPS drops down to the really low point (~24fps). So disabling G-Sync is not an option.

Really nice table!

But did you use "Fullscreen" mode or did you use "Fullscreen emulation"? I don't have a G-Sync monitor, but I get 24fps when V-Sync is enabled with "Fullscreen" mode, but I get 60fps when using "Fullscreen emulation".

I believe that the low frame rate in "Fullscreen" mode was an issue from back in Condor 2 (there was a workaround in the forums that involved modifying the Setup.ini file and changing the values of Numerator and Denominator). The simpler workaround is to use "Fullscreen emulation".

Interesting. I was using Fullscreen mode not Fullscreen Emulation. I was not aware of that problem with Condor 2.

[Bre901]

The recommendations in the first post have been updated in order to take into account the above discussion

[bluefang]

So I had some time to do some more testing tonight.

They key thing I figured out about G-Sync with Nvidia, is that it does not automatically default to the highest refresh rate of your monitor. It defaults to 60Hz. So if you have a monitor, like I do, which is capable of 144Hz, you have to set it to your desired refresh rate - and that is not in the 3D App Settings - it is in the Monitor resolution settings of the Nvidia Control Panel as seen in the screenshot below:

Once I changed that setting to 144Hz, I then was able to see Condor's fps default to 144fps with G-Sync turned on. Also, my system is not capable of maintaining a solid 144fps, so when it drops, I noticed the drop in framerate was reported by Condor's fps readout - and the monitor seemed to gracefully follow the fps as you would expect.

Again, was not able to replicate the rope-break issue - but I believe that issue is understood to be a situation where the Condor FPS is wildly different than the monitor refresh rate, which is not the case if you have G-Sync enabled.

Just thought I would update - as I was not aware of this setting, and had always assumed Windows would default to the maximum refresh rate of my monitor.

Also of note - I have read online reports that G-Sync does not work with well HDMI - but I am using a Display Port cable.

[zadmalck]

Hello everyone.

I had this problem of the cable unhooking when towing. I set the max FPS in NVIDIA in relation to my screen monitor. This solved the problem. Whether vsync was enabled or not in Condor. However, during the flight, the landscape display was jerky.

I don't know much about it. But since the problem has never occurred yet with Slovenia 3 but only with AA3 0.5, we should look to see if it is not a problem with the scene or the takeoff runway or the tile ....

Most of the time, my display is super smooth, with FPS that are between 100 and 200 FPS.

I have an I7 32 GB RAM laptop with RTX 3070. Emulated screen mode.

So there you go. Just some additional information.

The place where this is a problem for me is on certain departures from AA3 0.5 airfields and exclusively this scene so far. No worries on Slovenia 3.

Have a good flight everyone, on Condor 3 XC, of ​​course!!!

PS : Many thanks to J. Monteiro for pointing out the nature of my problem and directing me to this thread.

Code: Select all

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UPDATE :

I don't understand anything. I had disabled the max FPS in Nvidia to go back to how it was before. I changed MSAA supersampling from 4x to 8x with vsync disabled in Condor. Well, now the towing works!!!
Good luck to the experts ....


My SETTINGS :

Graphics options:

Visible distance : very hight
Trees Distance : Very hight
Terrain mesh quality : super fine
Terrain mesh fadeout : low
Objects level of detail : super fine
Textures quality : high
Canopy reflections : Reduced
Grass distance : High

Video options :

Fullscreen emulation
Screen Resolution : 1920x1080x32
MSAA supersampling : 8x
Vertical sync : Disabled

But if I switch back to MSAA supersampling: 4x, the towing fails.

I have 112 FPS in 8x and 198 FPS in 4x. So I will stay in 8X for now. It works fine.

[janjansen]

I have 112 FPS in 8x and 198 FPS in 4x. So I will stay in 8X for now. It works fine.

[strike]Please do keep vsync on (unless you are testing or actually want to trigger the bug). Its clear there are some random aspects to this, what may work one time may not work the other and you may be drawing incorrect conclusion. Enabling v-sync in condor should prevent the problem with tow as well as some other problems, it also prevents or reduces ugly screen tearing effects and has no downsides (for regular monitors). It shows a lower FPS number but a high number is meaningless, since your monitor cant show those extra frames.[/strike]

ignore the above, based on my testing below..

Thanks for the fpl and extra info though, Ill see if I can trigger the issue now.

[janjansen]

I have some BAD news. V-sync does not (always) solve the issue.
Condor V-sync enabled on a 75Hz monitor:



There does seem to be some relation with framerate and refresh rate but its definitely more nebulous. I did a lot of testing first on my normal 60Hz monitor. I could reliably reproduce the issue (thanks for the fpl zadmalck!) once I reduced my settings to get 200ish FPS, its a thermal heavy fpl, my AMD cpu does not like that. Then I played with nvidia frame rate limiter and even without vsync I found I could solve the problem reliably by capping the frame rate to just under 180 (178 being the magic number on my system on that fpl). Anything below that worked fine, above that I got the problem. I did ~20 flights

Then I switched to my VRR monitor which is set at 75 Hz (no G sync). With nvidia framerate limiter to to 178 it would snap. Tried 100, it snapped. Turned on v-sync in condor, it still snapped! Turned off nvidia framerate limited (kept condor v sync on), still snapped. Set my monitor to 60Hz with v-ysnc enabled , and it would not snap. Same pattern as with my first monitor, which isnt surprising, once I set it to 60Hz, everything is the same its just a physically different monitor, so anything below ~ 178 FPS would work, above the rope would snap.

All tests where done at 1920x1080 no MSAA because otherwise I cant get high enough FPS and my VRR monitor is only 1080p. Ill try later with different weather settings if that makes a difference and so I can get some higher performance at higher resolutions.

I dont know what to conclude from this, other than that we have no silver bullet yet. I have no idea if there is anything magical about 60 and 75Hz or if other tests would trigger with very different refresh rates. Anyone encountering the problem, Id say try setting your monitor to 60Hz and enable v-sync or at least cap your framerate but who knows?

If anyone with an intel system cares to help, please see if you can duplicate my findings at 60Hz, using the nvidia framerate limiter. I have a completely baseless hunch it might have something to do with thermal calculations messing up timing somehow, and that code runs way faster on intel. Wouldnt be surprised to see very different results. edit: scratch that. Just tried setting flats thermal activity to low, I get 500FPS now, at first glance, the magic number is still between 160FPS (no rope break) and 200FPS (rope break), could well be the exact same 178.

[wickid]

What I think the rope issue is (But only Uros knows for sure):

The tow rope breaking has to do with the physics being calculated every frame, but the glider not moving when the frame is not displayed by the monitor. So when the glider gets pulled by the rope and there are 3 frames being calculated but not displayed, the stress in the rope builds up when the physics are calculated but the glider doesn't move. This breaks the rope.

The other issue that was encountered in Condor2 as well, and may happen in Condor3: People would report a constant negative netto with very high framerates compared to the monitor refresh rate. This also has to do with the physics calculations being done for every frame, but the glider not moving between frames.

Because we (as the betateam) don't know for sure all the internal calculations we recommend limiting the framerate to the monitor refresh rate so the physics calculations are in synch with what is happening on screen. This is also reflected in the manual.

[janjansen]

The tow rope breaking has to do with the physics being calculated every frame, but the glider not moving when the frame is not displayed by the monitor. So when the glider gets pulled by the rope and there are 3 frames being calculated but not displayed, the stress in the rope builds up when the physics are calculated but the glider doesn't move. This breaks the rope.

Im sure there is truth in that, but I dont see then why at 75Hz + v-sync the rope still always breaks for me, and at 60Hz with any framerate below ~3x RR , it does not. And it also means we have no good solution for anyone running 75Hz monitors (or possibly higher), and I assume this could also happen with VR goggles at higher rates.

People would report a constant negative netto with very high framerates compared to the monitor refresh rate. This also has to do with the physics calculations being done for every frame, but the glider not moving between frames.

If that is supposed to have the same rootcause as the tow break issue, then Id like to test this too at 75Hz. If there is an fpl I could use or info about what framerates I should try to target to trigger the issue, please share or pm.

[wickid]

Don't know. I run VR at 90Hz (so also 90FPS) with V-synch on. I see no issues. But I also have no issues at 144Hz when playing on monitor only.

I've seen reports in Condor2 about it, and it was fixed with V-synch on. Same as the rope physics also being fixed by V-synch. As I said, I don't know the exact reason for these glitches. Only Uros can tell. Only he knows the exact physics calculations.

[janjansen]

Wild speculation: 60, 90 and 144 are even numbers. 75 is not.
Yeah I dont really believe that myself either, but its the only pattern I can see.

[6266]

The other issue that was encountered in Condor2 as well, and may happen in Condor3: People would report a constant negative netto with very high framerates compared to the monitor refresh rate. This also has to do with the physics calculations being done for every frame, but the glider not moving between frames.

Thanks for this explanation. I have had this at the beginning with my (in that days (2021?)) new laptop. Pit-R was a very big helper and supporter in that time. After reducing the frequency to 80 in nvidia and activating vsync in Condor it was gone. But it was a nightmare, when the Ventus became a Grunau Baby in final glide.

Now I have a theory that explains it. And I have set the frequency to 80 for C3 too now, hope to experience that never again ...