I’ve been testing the SU4 betas and wanted to share my findings because the first SU4 beta was extremely smooth and consistent for me, but since SU4 Beta 2 I’m now seeing random camera panning stutters, sluggish gameplay, lower FPS, and what feels like another round of performance degradation.
My System
CPU: AMD Ryzen 7 7800X3D
GPU: AMD Radeon RX 7800XT (slight OC, stable)
RAM: 64 GB DDR5 (XMP enabled)
Resolution: 1920×1080
Driver AMD Adrenalin (latest)
AMD Adrenalin Settings
Anti-Lag+: ON
FreeSync: Enabled (monitor + driver)
Chill: OFF
Enhanced Sync: OFF
FPS Lock: None (unlimited, managed by FreeSync + Frame Generation)
Radeon Image Sharpening: OFF (handled in-sim via FSR)
MSFS 2024 Graphics Settings
Display
Mode: Fullscreen
Resolution: 1920×1080
Anti-aliasing: TAA
Render Scaling: 100
FidelityFX Sharpening: 80–100
Frame Generation: ON
Max Frame Rate: OFF
V-Sync: OFF
Rendering Quality: Custom
Terrain & Objects:
Terrain LOD: 100–120 on ground, up to 250–400 in cruise
Objects LOD: 150 on ground, 50–80 in cruise
Offscreen Terrain Pre-Caching: Ultra
Displacement Mapping: ON
World & Scenery
Buildings: High
Trees: High
Grass & Bushes: Ultra
Plants: High
Rocks: High
Water Waves: High
Lighting & Shadows
Volumetric Clouds: Ultra
Raytraced Shadows: ON
Shadow Maps: 1024
Terrain Shadows: 1024
Contact Shadows: High
Ambient Occlusion: High
Reflections (Raymarched): High
Cubemap Reflections: 256
Light Shafts: High
Cockpit & Effects
Windshield Effects: Medium
Glass Cockpit Refresh Rate: Medium
Depth of Field: High
Motion Blur: OFF
Textures & Filtering
Texture Resolution: High
Anisotropic Filtering: 16x
Characters & Traffic
Characters (Quantity): Medium
Characters (Variety): Ultra
AI Traffic: All OFF (I use VATSIM instead)
Fauna: Ultra
Aircraft Usage
I primarily fly complex airliners such as the:
Fenix A320 family
FSLabs A321neo
PMDG 737/777
iFly aircraft
These are heavy on avionics and displays, but during SU4 Beta 1 performance was still excellent:
Ground ops felt smooth.
Taxi, takeoff, approach, landing were all fluid.
Cruise at FL370 was stutter-free.
Since SU4 Beta 2, however:
On the ground, performance feels slow, sluggish, and stuttery.
Even at cruise (FL370), I see random micro-stutters and less stable frametimes.
The mainthread issue seems to have returned, particularly in cruise, with the sim frequently spiking between GPU and MainThread limits.
Overall, the experience is noticeably less enjoyable compared to Beta 1.
What I See
SU4 Beta 1:
Smooth camera panning, very little stutter.
FPS consistent (~40–50 base FPS, ~80–100 with Frame Generation).
Mostly GPU-limited, clean frametimes.
SU4 Beta 2:
Random stutters/jitter when panning camera or switching views.
Gameplay feels sluggish/laggy, even when FPS counter shows stable values.
Lower FPS overall at identical settings.
MainThread spikes are back, especially in cruise, leading to instability that wasn’t present in Beta 1.
Summary
From my perspective, something changed between the first SU4 beta and SU4 Beta 2 that has:
Reduced raw FPS.
Introduced frametime instability (stutter on view changes).
Caused the sim to be both GPU and MainThread limited instead of primarily GPU-limited.
Affected performance across all phases of flight in heavy airliners (ground & cruise).
Brought back the mainthread bottleneck that felt solved in the first beta.
The first SU4 beta was one of the smoothest builds I’ve ever run in MSFS, so this regression really stands out. Hopefully this helps narrow down what changed, because SU4 Beta 1 performance was near perfect.
Thanks for your work - wanted to document my system, driver, and settings clearly so this feedback is reproducible.
Same here! It’s seems like there is either another round of memory leaks or a big disconnect between the sim . Now it’s at 13 fpsand my GPU (5090). In the air I am usually at 80-105 fps
Yes, I agree, there is something wrong somewhere in the last build…. It was way better in the two previous one on a performance side… Even if it is still better than SU3 !
Since the latest build, I have poor Performance again. It was much better in the First and Second Build. Even if you leave the Sim Running for hours, it will get worse. Its maybe the Same Bug again, like in Sim Update 3
Yep, same here. Performance was wonderful in Beta 1, worse in 2 and now with 3 we’re slowly getting back to where we came from it seems. Still much better than SU3, but certainly not as magical as the first release of SU4.
Yes, it is indeed mostly stuttering when panning views, but sometimes also on approach or when taxiing around the airport. In 1.6.3 there were almost no stutters.
1.6.3.0 → Nearly perfect. 1.6.5.0 → Performance still very good, but more stuttering when panning the camera. 1.6.7.0 → Worst performance of all three builds, with lots of stuttering when panning and while taxiing on the ground.
On top of that, with 1.6.7.0 I’ve already had two CTDs.
I’ve dealt with plenty of issues in MSFS2024 so far, but having a CTD without any error message must be at least 1000 flight hours ago back in the MSFS2020 days, long before SU15.
I’ve been flying the FSS 727 a lot lately.
In 1.6.5.0 the hydraulics didn’t work there (as in some other add-ons). In 1.6.7.0 that was fixed, but maybe that’s where the culprit lies that’s causing the CTDs.
Tomorrow I’ll try flying one of the routes where the CTDs occurred with a different aircraft.
I had fantastic experience on the first beta. Generally FPS are much smoother compared to Su3,
however.
I am getting significant stutters (particularly at night time) in heavy scenery. The sim can ground to a halt momentarily.
Otherwise, performance across the board is significantly better, but I agree with OP i think this build has introduced some nasty gremlins which make the performance unreliable.
Anyone else experiencing this?
p,s the audio pops when the cpu stutters are really still a thing.
I didn’t stay long in the 1st su4 beta because my favorite addon airplanes did not work, but the performance was great. I am on beta 3 now and my favorite airplane now works (for the most part, I still have a map light issue). In this beta the performance is greatly degraded. I also found that frame gen causes screen flickering in both 2D and VR. This flickering was also in the 1st beta.
I just did a flight from Los Cabos International Airport (MMSD) to Los Angeles (KLAX). Ground stutters happened even at MMSD (this was not the case in Su4B1) but i could cope with them as i was running locked 100fps and it felt smooth 99% of the time, same goes for cruise (no stutters there, weird thing is the moment my wheels leave the ground those stutters are gone) TLOD was at 100 at MMSD, in cruise up to 400, but the moment i touched down at IniBuilds KLAX it was an absolute slideshow!! crazy stutters and even freezing, the only solution? Putting my tlod down to 10(!!!). this is not normal behaviour, i owned Ini KLAX for a while and its never been this bad (only on SU3) In no way on my computer, id have to run LAX at a TLOD of 10 and still have issues. its an absolute nightmare. my OLOD on the ground at all times is at 130. I realize this should also easily be higher for my system but the sim does not like that. Please Asobo. this really needs fixing, as at this moment its almost impossible to fly into big airports…
Oh and to add to that: PLEASE FIX THE WASM (for 3rd party aircraft to function)_ AND THE JETWAYS!!
Its since 1.6.7.0
When Beta4 started Ive got noticably better performance and reduced VRAM footprint.
Sinca latest update 1.6.7.0 performance degraded signifiacntly and also VRAM usage went up. Its about same now as it was in SU3. But I don’t really see any difference in the image quality.
My System
AMD Adrenalin Settings
MSFS 2024 Graphics Settings
Aircraft Usage
What I See
Summary
