Set DCS Refresh Rate

[EntropySG]

I have the same GTX970 and used to be able to run at 60-70FPS too. Unfortunately I've had some issues ( http://forums.eagle.ru/showthread.php?p=2394701#post2394701 ) and I'm now using UltrMFCD to export my screens, but I'm stuck at 30FPS (max, goes down to 21) since I'm running in windowed mode.

 

I'm no expert in all the settings, any advice on what to change to get some decent FPS without putting everything in low res? (having spent the money ont the GTX it makes me miserable to run in low resolution)

 

Hi, I also use GTX970. Here is a post that helped me a lot with FPS:

taken from this thread

http://forums.eagle.ru/showthread.php?t=142979&page=3

 

OK, major revelation today: I tend to enable (when I remember to) 16x anisotropic filtering in NVCP whenever I update my drivers. Well, turns out that AF is killing my framerate -- I get 60FPS without, and 40 with.

 

After a very thorough uninstall of my 347.88 drivers, I gave the 352.86 drivers another try today. I found that I can get the same 60FPS with this set that I was getting with the 347.88 set, as long as I don't force AF (and actually, the same probably holds true with 347.88 ). I'm also getting identical FPS in PCARS as I was before, and, to boot, finally got SLI working in Witcher3 (about 40% scaling at 4K, not great, but helps tremendously).

 

So, I basically take back everything I said in the OP...352.86 now works just fine for me. I know a lot of people have had stability issues with this set (and I most definitely did with the previous 350.12 set) but I haven't had a chance to really test them yet, so can't comment on that yet.

 

Also, disable the mirrors, you dont really need them, at least in the A-10, and it will net you about 10FPS. Also, reduce the visibility on trees/bushes.

 

Let me know if that helps.

[Puma]

Multi monitor is a performance killer

 

I have the same GTX970 and used to be able to run at 60-70FPS too. Unfortunately I've had some issues ( http://forums.eagle.ru/showthread.php?p=2394701#post2394701 ) and I'm now using UltrMFCD to export my screens, but I'm stuck at 30FPS (max, goes down to 21) since I'm running in windowed mode.

 

I'm no expert in all the settings, any advice on what to change to get some decent FPS without putting everything in low res? (having spent the money ont the GTX it makes me miserable to run in low resolution)

 

 

I spent a lot of time tweaking settings and multi monitor configuration. My conclusion was that settings can make small differences, but multi-monitor makes huge differences. In the end i actually ended up exporting my gauges onto my primary flight display, a row along the bottom. On the 39" monitor it still leaves enough world view. Its a compromise to be sure, but i was happy to pay that price in exchange for 4k flying.

[Razi]

@OP

Are you saying that you set 60Hz (1) and DCS arbitrarily sets the refresh rate to 75Hz(2)?

(1) set in Windows or nvcpl?

(2) how do you verify that?

 

On a final note. DCS has built in tripple buffering or an alternative solution NOT requiring you to maintain FPS above your set refresh rate for the VSYNC to work. Search for posts by me with a keyword 'vsync'. DCS also doesn't cut your FPS by half as soon as hour FPS drops below your refresh rate.

 

Thanks for the reply, I have detailed most of this information already.

 

1. Displays are set to 60hz in Windows using nVidia control panel.
   
2. I verify this in two ways:
   
   1. 
      
   2. I check the monitors refresh rate.
      
   3. I confirm the monitors settings by monitoring the fps.
      * Both points done in windowed and fullscreen applications
      

 

A few other points:

1. 75hz isn't arbitrary. As I've said, my current monitors run at 75hz by default.
   
2. Vsync is not "working" when the fps and refresh rate are not in sync. If the fps is below the refresh rate the majority of the time, vsync is not working the majority of the time. Some software or GPU drivers have solutions for the instant that fps drops below the refresh rate. All of these solutions work to prevent the fps from being halved the instant the fps and refresh rate are no longer in sync either by buffering frames or temporarily disabling vsync, which works to minimize stutter, which you already know. They are not solutions to making vsync "work" if the system fps can barely reach the refresh rate.
   
3. The main problem is that my system cannot maintain 75fps as well as it can 60fps.
   

 

I'm getting the impression that most people in this thread think that having vsync enabled at 75hz is identical to vsync enabled at 60hz when the system fps is below 75, but above 60, the majority of the time. Vsync is a horrible solution to legacy technology that should have been done away with long ago and should not be used unless your system can maintain an fps equal to or greater than the refresh rate. I appreciate you taking the time to comment, but if you are one of them, we'll have to agree to disagree. Playing DCS at 60hz on my previous monitor is a much better experience than playing at 75hz with my current monitors because my system can maintain 60fps far better than it can 75fps (vsync and fps are intimately related!). It is hard to fly with lots of stuttering or tearing once you've experienced flying with almost no stuttering or tearing.

Edited May 26, 2015 by Razi
Turned out I wasn't brief...

[Razi]

Razi, there is no point to have Windows on 75 Hz and force DCS on 60, because those freqs must be the same if you want have synced framerate.

 

You must lower frequency of your monitor to the 60Hz value in Windows first. Than, I assume that DCS will automatically take that value for sync frame rate.

 

If you use Win7 here is setting for monitor refresh rate:

Right click on desktop->Screen resolution->Advanced settings->Monitor tab->Screen refresh rate

 

EDIT:

Uups, I replayed on post from February :doh:

 

Thanks for the comment, but I'm not sure you read carefully enough. Please re-read the first post.

 

Here is some help:

I have 75hz monitors and am able to set Windows refresh rate to 60hz in nVidia control panel

 

Read: I can set Windows to 60hz, but I cannot set DCS to 60hz. DCS changes the monitors back to 75hz.

Edited May 26, 2015 by Razi
Offered some help

[Razi]

@average_pilot Thanks for the guide. I'll look through and see what I can do.

[Bucic]

Thanks for the reply, I'll be brief since I have detailed most of this information already.

 

1. Displays are set to 60hz in Windows using nVidia control panel.
   
2. I verify this in two ways:
   
   1. 
      
   2. I check the monitors refresh rate.
      
   3. I confirm the monitors settings by monitoring the fps.
      * Both points done in windowed and fullscreen applications
      

 

A few other points:

1. 75hz isn't arbitrary. As I've said, my current monitors run at 75hz by default.
   
2. Vsync is not "working" when the fps and refresh rate are not in sync. If the fps is below the refresh rate the majority of the time, vsync is not working the majority of the time. Some software or GPU drivers have solutions for the instant that fps drops below the refresh rate. All of these solutions work to prevent the fps from being halved the instant the fps and refresh rate are no longer in sync either by buffering frames or temporarily disabling vsync, which works to minimize stutter, which you already know. They are not solutions to making vsync "work" if the system fps can barely reach the refresh rate.
   
3. The main problem is that my system cannot maintain 75fps as well as it can 60fps.
   

 

I'm getting the impression that most people in this thread think that having vsync enabled at 75hz is identical to vsync enabled at 60hz when the system fps is below 75, but above 60, the majority of the time. Vsync is a horrible solution to legacy technology that should have been done away with long ago and should not be used unless your system can maintain an fps equal to or greater than the refresh rate. I appreciate you taking the time to comment, but if you are one of them, we'll have to agree to disagree. Playing DCS at 60hz on my previous monitor is a much better experience than playing at 75hz with my current monitors because my system can maintain 60fps far better than it can 75fps (vsync and fps are intimately related!). It is hard to fly with lots of stuttering or tearing once you've experienced flying with almost no stuttering or tearing.

DCS is not other Games. I've been fiddling with DCS settings since the very beginning and I say [VSYNC* in DCS works even at 25 FPS]. My question: how do you verify that VSYNC is not working for you, as you claim?

[Razi]

I'm not sure you understand vsync. Before I reply, I need to know your understanding of vsync.

[Razi]

DCS is not other Games. I've been fiddling with DCS settings since the very beginning and I say [VSYNC* in DCS works even at 25 FPS]. My question: how do you verify that VSYNC is not working for you, as you claim?

 

I've read through your posts and I don't expect you to have to explain yourself when you've done extensive explaining already. You clearly understand vsync.

 

VSYNC is working to prevent tearing as it is designed to do. But it induces noticeable stuttering when the fps drops below the 75hz refresh rate.

 

I want to reduce suttering and tearing. Vsync does one of those things. Stuttering can be reduced by matching the refresh rate with a sustainable FPS. 60fps is sustainable and 60hz matches that. nVidia adaptive vsync tries to reduce suttering by temporarily disabling vsync the instant it drops below the refresh rate. DCS finds a nice fraction that matches the refresh rate and locks the FPS to it, but this induces more stuttering, in my experience, than nVidia's adaptive vsync. nVidia's solution works very well, but only if the system can maintain an FPS at the refresh rate the majority of the time. nVidia compromises screen tearing by temporarily disabling vsync and thus, if a system is constantly below the refresh rate, there is potential for a lot of tearing. If this is the case, then DCS's solution is better - for tearing only.

 

Until I upgraded my GPU I ran DCS at 30fps with nVidia's adaptive vsync at half the refresh rate with satisfactory results. On my new system with my 60hz monitor, DCS runs fantastic at 60hz. At 75hz, there is a noticeable suttering as vsync "works".

 

Locking my fps at 60 isn't the solution as I know you're aware. The solution, change my monitors to 60hz. Can you help me do that with your knowledge of DCS?

Edited May 26, 2015 by Razi
for clarity

[Bucic]

I've read through your posts and I don't expect you to have to explain yourself when you've done extensive explaining already. You clearly understand vsync.

 

VSYNC is working to prevent tearing as it is designed to do. But it induces noticeable stuttering when the fps drops below the 75hz refresh rate.

 

I want to reduce suttering and tearing. Vsync does one of those things. Stuttering can be reduced by matching the refresh rate with a sustainable FPS. 60fps is sustainable and 60hz matches that. nVidia adaptive vsync tries to reduce suttering by temporarily disabling vsync the instant it drops below the refresh rate. DCS finds a nice fraction that matches the refresh rate and locks the FPS to it, but this induces more stuttering, in my experience, than nVidia's adaptive vsync. nVidia's solution works very well, but only if the system can maintain an FPS at the refresh rate the majority of the time. nVidia compromises screen tearing by temporarily disabling vsync and thus, if a system is constantly below the refresh rate, there is potential for a lot of tearing. If this is the case, then DCS's solution is better - for tearing only.

 

Until I upgraded my GPU I ran DCS at 30fps with nVidia's adaptive vsync at half the refresh rate with satisfactory results. On my new system with my 60hz monitor, DCS runs fantastic at 60hz. At 75hz, there is a noticeable suttering as vsync "works".

 

Locking my fps at 60 isn't the solution as I know you're aware. The solution, change my monitors to 60hz. Can you help me do that with your knowledge of DCS?

I haven't witnessed any stuttering whatsoever when running at 75 Hz and 35 to 75 FPS. Thus I haven't investigated in forcing a select refresh rate so I can't help you with this particular task, sorry. Also, I'd place my bet that the stuttering in your case is caused by something else.

[Razi]

Also, I'd place my bet that the stuttering in your case is caused by something else.

 

Very possible. All I know is that with my hardware, running DCS at 1920 x 1200 @ 60hz with vsync is noticeably smoother than 4140 x 1024 (3 monitors) @ 75hz with vsync. I would like to see the later at 60hz. Windowed mode works, but requires me to first bezel correct my desktop before running DCS and undo it after, but I still see stuttering enough to be distracting. nVidia adaptive vsync does not appear to work in windowed mode - verified by the presence of tearing and seeing that the FPS is not locked. An SSD is next on the upgrade list, who knows? It is time to upgrade the hard drive anyways.

 

I had hoped that a simple config edit was all that was needed. DCS is the only game I have that does not have explicit options for refresh rate (I'm sure there are others, but I don't own them).

Edited May 26, 2015 by Razi
Typo

[HiJack]

SSD will solve much of the stutters

[Bucic]

Very possible. All I know is that with my hardware, running DCS at 1920 x 1200 @ 60hz with vsync is noticeably smoother than 4140 x 1024 (3 monitors) @ 75hz with vsync. I would like to see the later at 60hz. Windowed mode works, but requires me to first bezel correct my desktop before running DCS and undo it after, but I still see stuttering enough to be distracting. nVidia adaptive vsync does not appear to work in windowed mode - verified by the presence of tearing and seeing that the FPS is not locked. An SSD is next on the upgrade list, who knows? It is time to upgrade the hard drive anyways.

 

I had hoped that a simple config edit was all that was needed. DCS is the only game I have that does not have explicit options for refresh rate (I'm sure there are others, but I don't own them).

Not exactly a good set for comparisons there.

 

Also, you keep menmtioning the nVidia adaptive vsync. Disable it and test the built-in vsync option first.

[Razi]

Also, you keep menmtioning the nVidia adaptive vsync. Disable it and test the built-in vsync option first.

 

I have:

 

DCS finds a nice fraction that matches the refresh rate and locks the FPS to it, but this induces more stuttering, in my experience, than nVidia's adaptive vsync.

 

---

 

Not exactly a good set for comparisons there.

 

I have not been able to compare performance yet.

 

A proper and controlled comparison always has the same baseline hardware and software with one change. In my case I have not been able to create the same environment with my 75hz monitors as with my 60hz monitor - the one change being the monitors.

 

It may be that the 3 monitors, with an increase in resolution, is the culprit and I'd been fine with that and likely go back to my 60hz monitor. I got the old LCD panels for free and wanted to test the performance. But I have not been able to do a proper comparison in performance because I have not been able to replicate the same environment.

[Razi]

@Bucic I suspect we are at a dead end here as our experiences are different with DCS's vsync. In my experience DCS's vsync is inferior to nVidia's adaptive vsync - the comparison being done on the same system with my 60hz monitor - and this is entirely up to my own subjective perception. I have no empirical data for "stuttering"...

 

I appreciate the comments and that you took time to reply.

 

EDIT:

 

It appears FRAFS will work with FRAPS to enable frame time analysis. It may be sometime, but I should be able to get some empirical data for microstutter analysis. Should help me realize whether my perceptions are accurate or not. I'm also very interested in a good comparison between DCS's vsync solutions versus nVidia's (on my system). Should be fun!

Edited May 26, 2015 by Razi