Hunting for the stutter-free VR experience.

[WipeUout]

7 hours ago, Panzerlang said:

I think the combos of hardware and software are so complex there

Sorry it didn't work for your setup, probably something in PimaxPlay specifically for the Crystal came post 1.29 and causing degraded performance.  Yes, too many hardware/software configurations plus too many settings plus personal preferences for an infinite number of possibilities.

Edited January 4 by WipeUout
Typo

[Habu_69]

This may be widely known, but I just discovered it. Updating and tweaking nvngx_dlss.dll made for noticeably smoother and more vivid visuals using DLSS. YMMV.

https://forum.dcs.world/topic/356743-update-the-dlss-preset-used-by-dcs-to-remove-ghosting/

[Blackhawk163]

Grrr, updated to the new pimax play, and my smooth gameplay was nuked.

 

Hello stutter my old friend . . . 

[Moxica]

33 minutes ago, Blackhawk163 said:

Grrr, updated to the new pimax play, and my smooth gameplay was nuked.

 

Hello stutter my old friend . . . 

Happened to me also. Restart or "shake" (change a setting and press apply, restart DCS)the Quadviews companion. It was not active after update..

Edited January 4 by Moxica

[Panzerlang]

Can haz NVidia Reflex pls? 

"As of January 2025, NVIDIA Reflex is not officially supported in DCS World. NVIDIA Reflex is a technology designed to reduce system latency in games, primarily benefiting fast-paced, competitive titles. While DCS World has integrated technologies like NVIDIA DLSS to enhance performance and visual quality, NVIDIA Reflex has not been implemented in the simulator."

Edited January 5 by Panzerlang

[Panzerlang]

Gotta love AI.

"

what is 1:1 ram timing and can it reduce stutter?

ChatGPT said:

ChatGPT

What is 1:1 RAM Timing?

1:1 RAM timing refers to synchronizing the RAM speed (memory clock) with the memory controller's frequency or the Infinity Fabric (on AMD systems).

In simpler terms:

• RAM clock: The actual speed at which your memory operates.
• Controller clock: The speed at which the CPU's memory controller operates.
• 1:1 ratio: When these two operate at the same effective frequency, it reduces latency and ensures more efficient data transfer between the CPU and RAM.

---

1:1 RAM Timing in Practice

• On AMD Ryzen systems, the term often refers to setting the RAM speed (DDR frequency) to match the Infinity Fabric Clock (FCLK). For example:
  • DDR4-3200 RAM operates at 1600 MHz (half the DDR speed).
  • To achieve 1:1, the FCLK should also run at 1600 MHz.
• On Intel systems, it might mean aligning the memory clock with the CPU's uncore clock for optimal performance.

---

Can 1:1 Timing Reduce Stutter?

Yes, in certain scenarios, 1:1 RAM timing can help reduce stuttering, especially in games or applications that are heavily dependent on memory performance. Here's why:

1. Reduced Latency: Synchronizing RAM and CPU clocks minimizes the delays caused by mismatched frequencies.
2. Smoother Data Flow: A 1:1 ratio ensures the CPU and RAM communicate efficiently, preventing bottlenecks that can cause stuttering.
3. Improved System Stability: Running at a 1:1 ratio is often more stable compared to overclocking the RAM beyond what the memory controller can handle efficiently.

---

When Will You Notice an Improvement?

• Gaming: Memory-sensitive games (e.g., open-world or simulation games like DCS World or Cyberpunk 2077) may see reduced frame stuttering.
• Productivity: Tasks involving large datasets, like rendering or simulations, can benefit from lower latency.
• System Bottlenecks: If your system previously had mismatched clocks (e.g., high RAM speed with a lower Infinity Fabric clock), 1:1 timing can smooth performance.

---

How to Achieve 1:1 Timing?

1. AMD Systems:
   • Access BIOS/UEFI settings.
   • Set the RAM clock and FCLK to the same value. For example:
     • DDR4-3200 → FCLK at 1600 MHz.
     • DDR5 (if supported) → Follow similar principles with its scaling.
   • Test stability using tools like MemTest86 or Prime95.
2. Intel Systems:
   • Adjust the DRAM multiplier and memory controller frequency in BIOS.
   • Balance RAM speeds with CPU's memory controller capabilities.

---

Key Considerations

• CPU and RAM Limits: Not all CPUs and RAM can achieve high frequencies in 1:1 mode. Test stability carefully.
• Real-World Gains: The benefits might be minor in systems that are not memory-bound.
• Overclocking vs. Stability: Pushing RAM or FCLK too far can result in crashes or instability, negating any performance gains.

If you’re experiencing stutter, aligning RAM timings and ensuring a 1:1 ratio can be a good step in your optimization process!

4o

 

You said:

gigabyte z790 mobo, 13900k cpu and 6400 ram, can i do it with these?

ChatGPT said:

ChatGPT

With a Gigabyte Z790 motherboard, an Intel Core i9-13900K, and 6400 MHz RAM, achieving a 1:1 ratio (synchronized RAM and memory controller clock speeds) is unlikely due to the architecture of Intel's 13th Gen CPUs. Here's why and what you can do:

---

1. Intel's Memory Controller Design

• Intel's 13th Gen CPUs (like the 13900K) use a Gear Mode system to manage memory:
  • Gear 1: Memory controller runs at the same speed as the RAM (1:1 ratio).
  • Gear 2: Memory controller runs at half the speed of the RAM (2:1 ratio).
  • Gear 4: Memory controller runs at one-fourth the speed of the RAM (4:1 ratio).

With high-speed RAM like DDR5-6400, the memory controller defaults to Gear 2 for stability, meaning the controller runs at 3200 MHz while your RAM runs at 6400 MHz (effective). This is necessary because running the memory controller at 6400 MHz is beyond its capability.

---

2. Can You Force a 1:1 Ratio?

• For DDR5-6400 RAM, a Gear 1 (1:1) ratio is not feasible. The memory controller can't handle such a high speed without instability, even on high-end CPUs like the 13900K.
• Lowering the RAM frequency to a range like DDR5-4800 or DDR5-5200 might allow for Gear 1 operation, but this defeats the purpose of using high-speed RAM.

---

3. What Can You Do Instead?

While you can't achieve a 1:1 ratio at DDR5-6400 speeds, you can optimize your setup for the best performance:

Enable XMP/EXPO Profiles

• XMP (Extreme Memory Profile) ensures your RAM runs at its advertised speed (e.g., 6400 MHz) with optimal timings.
• Access the BIOS and enable the appropriate XMP profile for your RAM.

Optimize Gear 2 Performance

• Gear 2 is designed for high-speed DDR5 and works efficiently on Intel 13th Gen CPUs. Stutter is unlikely with this configuration.

Adjust Sub-Timings and Latency

• Fine-tune RAM timings in the BIOS for lower latency. Tools like MemTest86 can help you test stability after adjustments.

Test Stability

• Use benchmarks like AIDA64 or Cinebench to ensure the system runs stable at your desired settings.

Balance Performance

• If you're concerned about stuttering or latency, consider slightly lowering the RAM frequency (e.g., DDR5-6000 or DDR5-5600) while tightening timings. This can yield a better balance of latency and speed.

---

Conclusion

With a Z790 motherboard, 13900K CPU, and DDR5-6400 RAM:

• Achieving a 1:1 ratio is not possible at 6400 MHz due to Intel’s Gear Mode limitations.
• Gear 2 mode is perfectly optimized for DDR5-6400 and should provide excellent performance with minimal stuttering.
• For the best results, enable XMP and, if desired, fine-tune RAM timings or frequencies for reduced latency.

This setup is high-end, and you should enjoy excellent gaming and productivity performance even without a 1:1 RAM timing.

4o

 

The video talks about the CPU render-queue. What's the betting this might be a significant cause of micro-stutter?!

[Panzerlang]

1. Why Reflex Would Benefit DCS World

• Complex Input Processing: DCS involves precise control inputs from peripherals like HOTAS setups, rudder pedals, and VR hand tracking. Reducing input-to-display latency would make these controls feel more responsive.
• VR Gaming: Many DCS players use VR headsets, where input latency and frame timing are critical for an immersive and smooth experience. Reflex could enhance VR gameplay by reducing motion-to-photon latency.
• High Visual Demand: DCS is a CPU and GPU-intensive simulator. By optimizing the rendering pipeline with Reflex, you could experience smoother interactions, even under heavy system load.

---

2. How Reflex Works in This Context

• Minimizes Latency: Reflex reduces the time between input (e.g., moving your joystick) and seeing the result on the screen. This is especially valuable in combat scenarios where rapid reactions are key.
• Balances CPU and GPU Load: DCS can bottleneck on either the CPU or GPU, depending on settings. Reflex ensures the GPU doesn't queue up excessive frames, keeping the system responsive.
• Improves Frame Timing: By reducing latency and synchronizing frame generation with input, Reflex could help mitigate microstuttering, enhancing the fluidity of the simulation.

---

3. Current Limitations

• Not Currently Supported: Reflex is not yet available in DCS. NVIDIA Reflex requires integration by the game developers, and Eagle Dynamics (the developers of DCS) haven't announced plans to implement it.
• Complexity of DCS: The sheer complexity of DCS’s rendering engine and physics might make Reflex integration a challenging task for developers.

---

4. Alternatives for Latency Optimization

While waiting for Reflex, you can reduce latency and stuttering in DCS with these steps:

• Use DLSS or FSR: If your GPU supports DLSS, enabling it can help improve performance and reduce input lag by lowering rendering loads.
• Enable G-Sync or FreeSync: This can help smooth out frame delivery, reducing perceived latency.
• Lower Latency Settings: Enable NVIDIA’s Low Latency Mode in the NVIDIA Control Panel.
• Optimize Settings: Fine-tune in-game settings to balance CPU and GPU load, particularly in VR or high-resolution setups.
• Update Peripherals: High-quality, low-latency input devices (HOTAS, pedals, etc.) can make a noticeable difference.

---

Conclusion

If NVIDIA Reflex were integrated into DCS, it could provide a huge boost in responsiveness and smoothness, particularly for VR and competitive gameplay. For now, leveraging tools like DLSS, Low Latency Mode, and careful hardware optimization can help you achieve a similar effect.

Let’s hope Eagle Dynamics considers Reflex integration in future updates—it could be a game-changer!

[Blackhawk163]

And after being resigned to what I thought was a return to stutter, it’s now gone. I did mess about with some openxr settings. I had NIS upscale on, but then turned it off in favor of CAS, turned off turbo, Hags and enabled them subsequently disabled NIS in DCS and not in openxr (ghosting was really bad on aircraft) then dlss, but then disabled all that. Re-enabled HAGS (gained back 20% performance) at this point I was just looking for the best performance to visual settings as I had given up on trying to get back to stutter free.

Then I ran a free flight, and as I was looking over the side for some BDA on some practice targets when I noticed the lack of stuttering. I continued on at various alts, and yup, gone.  I’m still running the combination of FFR and Quadviews. 
 

So freaking weird. 

Edited January 9 by Blackhawk163

[Ready]

5 hours ago, Blackhawk163 said:

And after being resigned to what I thought was a return to stutter, it’s now gone. I did mess about with some openxr settings. I had NIS upscale on, but then turned it off in favor of CAS, turned off turbo, Hags and enabled them subsequently disabled NIS in DCS and not in openxr (ghosting was really bad on aircraft) then dlss, but then disabled all that. Re-enabled HAGS (gained back 20% performance) at this point I was just looking for the best performance to visual settings as I had given up on trying to get back to stutter free.

Then I ran a free flight, and as I was looking over the side for some BDA on some practice targets when I noticed the lack of stuttering. I continued on at various alts, and yup, gone.  I’m still running the combination of FFR and Quadviews. 
 

So freaking weird. 

Don't touch it anymore!! haha. I have the same happening too frequently. And then for some reason it all turns to mush again after a couple of days without any clear adjustments.. 

[jnr4817]

I just got my CL, coming from a G2. I uninstalled all of the openxr and related apps to use WMR with G@. I uninstalled quadviews and any related stuff. The only thing I kept was WMR incase the CL was broke on arrival. I Dl'd pimax play, redownloaded quad views, and download qv companion. I installed pimax play, the mbuccia quadviews, and then qv companion. I started up pimax play, adjusted some settings, clicked use quad views button and launched dcs. seemed work well. I kept all the same DCS i was using with the G2. Man this game looks good and performs well. Using 72hz and higher render quality with mostly max dcs settings my qv companion settings are pretty liberal. so far pretty happy.

[ischicopter]

@Panzerlang

 

Reflex is not going to fix your problem. In fact I believe it is specifically not recommended to use Reflex in VR. You can try and force it ON in the NVCP.

Copying & pasting whole pages from Chatgpt is also not going to help btw.

 

Maybe you could to a TLDR of all the things you already tried? 

My suggestion would then be to revert everything to their "default" settings. Especially any kind of "allround tweaks" one would find a typical youtube tutorial, like GPU scheduling, specific NVCP settings, mild overclocks etc. 

Also uninstall any mods and anything VR related and start over with a vanilla install (DCS and Pimax/SteamVR). Revo uninstaller is a good tool to get rid of any remaining possibly corrupting files and registry entries.

 

 

[Panzerlang]

1 hour ago, ischicopter said:

@Panzerlang

 

Reflex is not going to fix your problem. In fact I believe it is specifically not recommended to use Reflex in VR. You can try and force it ON in the NVCP.

Copying & pasting whole pages from Chatgpt is also not going to help btw.

 

Maybe you could to a TLDR of all the things you already tried? 

My suggestion would then be to revert everything to their "default" settings. Especially any kind of "allround tweaks" one would find a typical youtube tutorial, like GPU scheduling, specific NVCP settings, mild overclocks etc. 

Also uninstall any mods and anything VR related and start over with a vanilla install (DCS and Pimax/SteamVR). Revo uninstaller is a good tool to get rid of any remaining possibly corrupting files and registry entries.

 

 

Brand new install of the OS and DCS etc and I think DCS is running as well as it can, all the tweaks have accumulatively been very successful.

[Panzerlang]

I did a performance comparison, fwiw. My personal takeaway is that ED need to look at why DCS is whaling on a single core, if that is actually what's going on. It certainly appears so and would explain the stutter..
 

 

[WipeUout]

On 1/11/2025 at 7:33 AM, Panzerlang said:

I did a performance comparison, fwiw. My personal takeaway is that ED need to look at why DCS is whaling on a single core, if that is actually what's going on. It certainly appears so and would explain the stutter..

Entirely possible.  As an example when I play the same mission on my sim rig vs. playing from my DCS server on my home network, the CPU shows lower frametime as the burden is taken in part by the server's CPU.  In general, stutters appear when frametimes (GPU or CPU) come close or exceed 11 ms (for 90hz) but every time I had stutters with frametimes well below 10ms, it was caused by something else such as something running in the background or another setting in windows/BIOS/NVIDIA/etc.

I do think that multithreading can be improved but there might be limitations because of the (old) DCS rendering engine not fully taking advantage of multi-core processors.  This might change when ED transit to vulkan.

BTW, I tried the same mission, following the as much as possible same path you used in your video and did not experienced any stutters.  My max CPU frametime went to 7.6 ms and my GPU always stayed under 10 ms, I use OXRTK to track metrics.  My DCS settings are quite different though, see below.  My rendering pixel count (from QVFR log) is down to 11 301 800 from 23 611 520 and my HMD refresh rate is at 90hz.

 

Edited January 12 by WipeUout
update

[Moxica]

On 1/11/2025 at 5:33 AM, Panzerlang said:

My personal takeaway is that ED need to look at why DCS is whaling on a single core, if that is actually what's going on. It certainly appears so and would explain the stutter..

Absolutely. The ball is in ED's court. There is no more I can do.
 

[Panzerlang]

3 hours ago, Moxica said:

Absolutely. The ball is in ED's court. There is no more I can do.
 

Wow! The very definition of 'picture perfect'! 36% package with one core getting a 100% flogging. 

[LucShep]

5 hours ago, Moxica said:

Absolutely. The ball is in ED's court. There is no more I can do.
 

Yep.

You see, the fixes and adoption of a more advanced game engine is inevitable for ED. It's no longer a "it'd be nice" as we thought many years ago, it became a necessity.

With the ammount of much higher polycount maps and objects (aircraft and not only), and a gazillion of overkill 32-bit 4K/8K textures (in everything) that are now being added to the game, plus adding more complex scripts for avionics, systems, weapons, AI, weather and environment effects (and also of more complex missions) and etc, it can only be delayed for so long until the game becomes unusable as is.

Because it got to a point where you spend absurd money for the strongest hardware but get only a small fraction of its benefit, due to game code/engine constraints.

If you've upgraded your system recently, try other games and, in comparison, you'll see a monster jump in performance...

 

Edited January 13 by LucShep

[Panzerlang]

1 hour ago, LucShep said:

Yep.

You see, the fixes and adoption of a more advanced game engine is inevitable for ED. It's no longer a "it'd be nice" as we thought many years ago, it became a necessity.

With the ammount of much higher polycount maps and objects (aircraft and not only), and a gazillion of overkill 32-bit 4K/8K textures (in everything) that are now being added to the game, plus adding more complex scripts for avionics, systems, weapons, AI, weather and environment effects (and also of more complex missions) and etc, it can only be delayed for so long until the game becomes unusable as is.

Because it got to a point where you spend absurd money for the strongest hardware but get only a small fraction of its benefit, due to game code/engine constraints.

If you've upgraded your system recently, try other games and, in comparison, you'll see a monster jump in performance...

 

Seems to me, 'all they need to do' is stop the code from maxing out a single core. If the load was spread evenly (as in 35% on ALL cores, instead of 35% on all the cores but the one getting hit for 100%) I think the stutter would be fixed.

It's only my inexpert opinion but it does appear the MT coding is currently fubar.

[freehand]

I do not suffer from a core maxed out is every one suffering from this ?

[Panzerlang]

1 hour ago, freehand said:

I do not suffer from a core maxed out is every one suffering from this ?

No idea. It might be hardware dependent but given how many people with high-end kit are suffering from stuttering, at some level or other (it can be mitigated with a shed-load of tweaks that we shouldn't have to be doing) I think it's a good guess that the over-loaded single-core scenario is a good candidate.

[Qcumber]

I am not getting a single core maxed out either. Until this point I had thought it was an Intel thing but Moxica has an AMD CPU. 

 

[Aapje]

4 hours ago, Panzerlang said:

If the load was spread evenly (as in 35% on ALL cores, instead of 35% on all the cores but the one getting hit for 100%) I think the stutter would be fixed.

That's not how it works. It's impossible to spread the load exactly evenly unless the work is all the same, which is not the case for games. And if workloads have interdependencies, then you can't just move part to a different core without causing big slowdowns.

That doesn't mean that the code can't possibly be optimized much better, but you will never get infinite scalability.

[LucShep]

5 hours ago, Panzerlang said:

No idea. It might be hardware dependent but given how many people with high-end kit are suffering from stuttering, at some level or other (it can be mitigated with a shed-load of tweaks that we shouldn't have to be doing) I think it's a good guess that the over-loaded single-core scenario is a good candidate.

No, no.
It goes beyond workload spread on CPU cores, that on itself won't solve the problems.

How it all works as a package for all the demanding content that is being placed, right from the start, and how it manages all resources (CPU, GPU, RAM, Storage and basically all the I/O load) is what matters.

DCS has many of its roots going back over 20 years, historically hogging resources like a pig since release back then, and you know what they say about "lipstick on a pig".... 

 

Edited January 13 by LucShep

[Panzerlang]

Well, maybe it's apples and oranges but IL2 (single core) thrashes the GPU quite nicely but barely touches the CPU, assuming the Game Bar widget is accurate. That reports 7% CPU usage (highest I saw at least).
Yeah, kind of hard to believe the widget's accuracy, one would think 87% GPU would be pushing at least one core on the CPU way higher than 7% (I'm assuming the GPU render-load can't be split over multiple cores).

[Wali763]

I havnt read through all the thread, but what Im missing is the ground level, that participant consent on, for discussion. 

What is "stutter", was is "smooth"?? This is very subjective and many people consider someting smooth, that I do not eg.

Ive be striving for smooth gameplay on my G2 ever since I had the RX6950XT. Starting from then, I tried to get to 90fps and accepted lowering the graphical settings for that.

Now I have a 4090 and a 7800x3D and am close to that goal or at least within my acceptable range.

I tried many thing suggested and many did not work for me. Overall I have a rather clean install of Win10 with many services disabled. As of writing this I have 2 main process (Browser, Taskmanager to check) and 41 background processes running.

One thing, that reduced some of the spikes in the chart below was, setting my DDR5-6000-CL30-36-36 RAM to tightest timings in my UEFI (MSI MB). 

One thing, that I cant follow is the discussion over imput lag. The offerings like Nvidia Reflex are meant for gamers in fast paced games like online Firstpersonshooters, where you usually have 300+fps. DCS is too low fps for that and also our input dont need that precise as in mentioned shooters.

Latency overall, as mentioned above with my thigher RAM-timings still does to have some impact.

Below is a a fps and frametime-chart from Afterburner for an ~15 minute mission in an remote area of Iraq. As you can see fps is almost all the time at 90, sometimes 89. Frametimes at 11, somtimes spiking up to 35ms. This spikes occur usually, when someting happens, like an explosion. For every even minor spike I get a perceivable stutter, so to me this is not sutterfree. But within my personal exaptable range. The huge spikes at the beginnng and the end are of course because of loading the mission and closing it.

It would be nice if other people could also show such a chart of their own, so I and we can understand better, what those player mean.

 

Edited January 15 by Wali763