Guide: Stutter fix for IL-2 Great Battles w/Lossless Scaling

[Kubert]

This guide is a little longer than I originally intended because I added a lot of explanation. But it's easier as it looks (5 easy steps) and it's seriously worth it.

 

Who is the target group for this fix? Flat screen users who are experiencing stutter in crowded areas while playing campaigns or careers. Unfortunately not VR users. The fix works only for games in windowed or borderless windowed mode.

What does it require? Lossless Scaling program and a more or less modern system. (RTX GPU or AMD equivalent)

What is Lossless Scaling? A program that overlays the game and adds LSFG frame generation.

How does it work? If I understand correctly...LS removes stutter, or better said, hides it, by adding "fake" frames between the "real" frames, which makes the image smoother. 60fps looks like 120fps, at least on a 120Hz monitor.

 Are you sure it works? Yes, at least for me. I tested it on very crowded missions. The first 5 missions of the Sky Nomads campaign, the first mission in Iron Wind and as the final boss the first two missions of the Steel Birds campaign. The stutter disappeared, or was reduced by let's say 95%, in the most intense places. I didn't spare the PC at all and I had the in-game recording turned on entire time to spice things even more.

Is it a mod? Does it change the game files? No, it's an overlay. It doesn't interact with the game files. They remain intact.

Does it have any shortcomings? The only thing I noticed is that it partially blocks the Nvidia Experience overlay. Nothing more. In-game screenshots and in-game recording work and MSI Afterburner is fine too. I haven't tried anything else.

Where can I get it? On Steam for €6.89.

 

Before I continue, I need to explain what my goal was: at 2560x1440 resolution on a 120Hz monitor to achieve a stable 120fps (actually 118, but I'll round it up...I'll explain later) with v-sync enabled and zero stutter.

 

Now the guide itself:

Step 1: Set the graphics in the game according to your preferences. Of course, within reasonable limits.  The only thing that must be set in the game is turned off Fullscreen mode and V-sync. Turn off the game after you are done. These are mine:

Step 2: In the graphics card drivers, for the IL-2 Sturmovik, set Maximum Frame Rate to 59, V-sync to On, Triple Buffer to On.

Note 1: Why not 120fps when that's the goal? Now we need half of that, because the LS program will double it.

Note 2: Why 59fps? Because I have experience that locking 1-2 fps below the monitor refresh rate stabilizes frame pacing and sometimes works as an anti-stutter itself. Unfortunately not in IL-2, but I set it anyway, just to be safe.

Note 3: V-sync and Triple buffer are probably not necessary, but I left them On, they don't hurt anything...so whatever.

 

Spoiler

It is in the weird language, I put it here just for the reference. 

 

Step 3: In your graphics card drivers, set V-sync for Lossless Scaling to Fast. This is very important, it will eliminate screen tearing.

 

Spoiler

 

Step 4: Turn on Lossless Scaling and set: 

Step 5: Now, turn on Lossless Scaling (you probably have it), turn on IL-2, while in the game menu Alt-Tab back to Lossless Scaling, click on "Scale" in the top right corner and before the 5 second countdown ends, Alt-Tab back to the game. Now numbers should appear in the top left corner of the game...for me it's 59/118 (actual frame rate/"perceived" frame rate). And that's it...you can play without stutter now. This Step 5 needs to be repeated before every game, but it's a small price to pay for the gain.

I currently have an RTX 5080, but according to monitoring via MSI Afterburner it is only about 50-65% utilized. This means that it has a lot of headroom and this frame gen does not require extremely powerful hardware. RTX 30xx and 40xx owners should be fine. I think even a 20xx, especially if the goal is 1080p and 60fps. This guide is just a blueprint, not the only possible solution, you can experiment.

Personally, I never experienced scripted campaigns to run so smoothly before. As if there weren't dozens of active units around. 🤯 It also works with other games. For example, Elden Ring has a hardcoded 60 fps lock and with the same LS settings it can be played as if it were running at 120 fps. Very useful program.   

I hope this will help someone. 

Edited February 16 by Kubert

[Koziolek]

Does it work for VR?

[Kubert]

48 minutes ago, Kubert said:

Unfortunately not VR users. The fix works only for games in windowed or borderless windowed mode.

As far as I know, it doesn't. Maybe some workaround exist, but I didn't search for it. I don't own VR, so...

[robzerg]

Does anyone know if the game will run in an effectively full‑screen mode when using this software? I’m hoping it will fill the entire display rather than sitting as a small window in the centre. I’m on a 4K monitor but play the game at 1080p — will Lossless Scaling stretch the image to full screen?

 

[Kubert]

I never used different than native resolution of the monitor for the game. As far as I know, Lossless Scaling don't change how tha game is displayed. If the game itself, without LS, runs as intended...meaning in borderless windowed mode, at 1080p, but covering entire screen of 4K monitor...then it should be as well with LS. 

[robzerg]

Thanks Kubert; I've installed Lossless Scaling and all seems to be working well; it automatically upscales the game from windowed mode to fill the screen :-)

I suspect I need to tweak the settings a little to get the optimum output on my relatively low-end PC, but it certainly makes the game appear smoother on screen with better anti-aliasing and less stuttering - especially when blasting an enemy aircraft up close!

The only thing to note is that LS has some GPU overhead, so the input framerate is reduced from the previous (pre-LS) value, before being increased by LS.

[robzerg]

Update: I think I have found the optimal settings, which greatly improves the visual fidelity of the game for me - making a 1080p game look and feel like 4k!

[Kubert]

Interesting, I never used LS for resolution scaling, only for frame generation. Good to know it works as well. 

[robzerg]

It's possible to use FSR upscaling too which results in better image quality, but there is a slight performance hit with it. Certainly LS is a good option for older/lower powered machines.  It's amazing how the jump from ~30 fps to ~60 fps makes the feeling of flight much more convincing, and helps with my aim and tracking of targets.