[OTH] Trigger ALLM, G-Sync, and AMD FreeSync off then using powershell or command prompt

[jakubgt]

I am using LGTVCompanion and am trying to create a .bat file to toggle ALLM, VRR, and FreeSync off/on to fix a screen flickering issue on boot for my LG C3.

Is there any way this can be done?

[JPersson77]

I think these are good candidatres:
-gameoptimization [off|on] - set VRR and G-Sync
-inputoptimization [auto|on|standard|boost] - Prevent Input Delay
-freesync [off|on] - set AMD Freesync Premium

https://github.com/JPersson77/LGTVCompanion/blob/master/Docs/Commandline.md#picture-commands-lgtv-companion-and-lgtvcli

[jakubgt]

I think these are good candidatres: -gameoptimization [off|on] - set VRR and G-Sync -inputoptimization [auto|on|standard|boost] - Prevent Input Delay -freesync [off|on] - set AMD Freesync Premium

https://github.com/JPersson77/LGTVCompanion/blob/master/Docs/Commandline.md#picture-commands-lgtv-companion-and-lgtvcli

I followed the suggestion to use the global commands (-gameoptimization, -freesync, -inputoptimization) for my script. I seem to be getting a "cannot relay luna response" error". The failure occurs in Phase 1 of my script, before I have even reset the GPU driver.

-sethdmi4 works (returns returnValue:true).

-gameoptimization off fails immediately with Cannot relay luna response.

I also see this error in the log: exception: handshake: An existing connection was forcibly closed by the remote host.

This implies the issue is not caused by the GPU handshake (since it happens before the reset). It seems the TV is accepting "Input" commands but rejecting "System Settings" commands via Luna.

Log Snippet:

[Phase 1: Pre-Reset]
Attempt 1/3 : -sethdmi4 Lg C3 42
Result: Success

Attempt 1/3 : -gameoptimization off Lg C3 42
Result: {"Device1":{"info":"Cannot relay luna response."}}
(Repeated failures for -freesync and -inputoptimization)

.bat code: https://pastebin.com/PQKR5Q52
.ps1 code: https://pastebin.com/5RtYJNtg

Is there a specific "wake up" command or permission level required for gameoptimization that is different from sethdmi?

RTXReset-20260204-134154.log

[JPersson77]

"cannot relay luna response" is not an error. It is just to inform the user that the Luna API will not generate a useful response. Usage of the Luna API is a semi-undocumented way to communicate with the TV for some commands. Unfortunately it is a black hole and will just eat comms.

The log is generated by the service, not LGTVcli.exe. So any references to "handshake: An existing connection was forcibly closed by the remote host" must be connected to commands sent to LGTV Companion.exe (or the automatic management of the TV by the app)

Maybe it is intended, but I think the commands should utilize double e quotes like so: -gameoptimization off "Lg C3 42"

Did you confirm in the settings of the TV that the commands you sent did not work?

To avoid the handshake issues (which may cause delays or interrruptions) please try to enable "persistent connections + keep alive" for the TV (in LGTVC device configuration). And then send the commands to lgtv companion.exe, instead of LGTVcli.exe. LGTVcli uses the older sync websocket model while lgtv companion has been updated to a newer async mode and is much more resilient. It is on the todo to revisit this for LGTVcli.exe too.

Lastly, if I may. I think you may want to investigate if it is your HDMI-cable that cause flickering. This is by a large margin the no 1 cause for flickering issues. Secondly I would enable "always ready" on the TV. As applicable.

[jakubgt]

Thank you! The script goes through now, I just need to wait for the flickering to occur to fully test.

I just ordered the new Zeskit Maya 96gbs with the new HDMI 2.2 standard. I will give an update with my findings including the source if the .bat and .ps1 file temporarily fixes the issue until the next reboot.

[JPersson77]

Good to hear! Annoying issue - I hope you will get it resolved! Another thing worth trying if you haven't already is the WIN+CTRL+SHIFT+B shortcut to reset the nvidia driver. Not sure what it does technically (how much is reset) but it seems to be useful for some to recover from typical black screen crashes

[jakubgt]

Okay so the script seems to work very well when I use it. This script fixes the common "black screen", "flickering", handshake, and other issue on Windows when using an NVIDIA GPU with an LG OLED TV. Persistent Connection MUST be checked for this to work in the LGTV companion app. By automatically cycling the TV's gaming features and resetting the GPU driver, it forces a clean HDMI handshake, restoring full bandwidth functionality.

The script does the following:

Restores 120Hz & HDR: Fixes boot states where the screen is locked to 60Hz or HDR is greyed out/washed out.
Fixes G-Sync/VRR Flickering: Toggles Game Optimizer modes off and on to eliminate handshake shimmer or flickering.
Resets NVIDIA GPU Driver: Performs a software-level "unplug and replug" of the graphics card via PnP to force a fresh connection without rebooting.
Restarts Windows Explorer: Automatically kills and restarts explorer.exe to fix any taskbar glitches or frozen icons caused by the display reset.
Zero-Error "Async" Mode: Uses the robust asynchronous connection method of LGTV Companion to ensure commands work even if the TV is slow to respond.

1. Download Reset_GPU_LGTV.ps1 and Launcher.bat. They are currently .txt files, be sure to change them to the correct file type.
2. Edit Launcher.bat
3. Fill in the blank spots in the "USER CONFIGURATION" section:
   o LGTV_DEVICE: Enter your TV's Friendly Name exactly as it appears in the LGTV Companion app (e.g., LG C3).
   o LGTV_HDMI: Enter the HDMI port number your PC uses (e.g., 4).
   o GPU_HINT: (Optional) If you have multiple GPUs, enter the model name (e.g., RTX 4090). Otherwise, leave it as NVIDIA.
4. Save the file.
5. Run Launcher.bat as Administrator.

Hopefully this helps! The new HDMI 2.2 certified 96gbps cables should be coming in late next week, so I'll let everyone know if it fixes the issues some of us have.

Edit: The new Zezkit Maya HDMI 2.2 does not fix the issue. This script has been the only method I could think of for resolving this issue.

Launcher.bat.txt
Reset_GPU_LGTV.ps1.txt

[JPersson77]

Thanks, I'll leave the thread open for anyone facing these issues. Please @jakubgt share how/if the updated cable affects your issue