LMU shadow strobing with ARC

[Saabjock]

The issue of flickering/strobing shadows and the inability to run Le Mans Ultimate with rear-view mirrors or in-game trackside videos displaying, still needs to be addressed.

I've searched the site and it has been reported numerous times...over several months.

I have tried multiple Intel drivers...all the way to the current 32.0.101.7029.

They've all exhibited the same behavior, i.e ....flickering or flashing on surfaces, when attempting to cast shadows.

It is clearly evident in the attached video on the pitwall adjacent to the pit box.

It is also there on the floor when exiting the pit to go on track.

It can also be seen where any overhead object tries to cast a shadow on any object below.

See the attached video....

Intel ARC_2025 09 04 06 16 37

[Mike_Intel]

Hello Saabjock,

Thank you for posting in Intel community Forum.

For me to better understand and diagnose the issue further, let me ask you to provide detailed responses to the following questions. This information will help me isolate the problem and determine the most appropriate course of action moving forward.

1. What is the model of your Graphics controller?
2. What is the model of your processor?
3. What is the brand and model of your system?
4. Was it working fine before?
5. If yes, what was the last change made before the issue started?
6. How did you update the driver?

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[Saabjock]

Please see the attached Intel SSU.

The data in that report was captured using the Intel 32.0.101.7028 driver.

I have since switched to the 32.0.101.7029 driver but I have gone through approximately six drivers previously.

It exhibits the exact strobing, even with that (latest) driver.

My card is the A770LE.

There is no overclocking on anything in the system....all drivers and motherboard BIOS are updated to the latest.

[Mike_Intel]

Hello Saabjock,

Thank you for the update.

Can you try re-installing the latest Graphics driver using DDU method and update me if you are still having the same issue.

Please refer to the link below for the steps and the download link of the latest driver:

How to Use the Display Driver Uninstaller (DDU) to Uninstall a...

Intel® Arc™ & Iris® Xe Graphics - Windows*

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[Saabjock]

Every driver...including the current one were installed by using DDU in safe mode to remove the previous one.
A clean install is always selected.
The issue is the same for the previous five Intel drivers.
In addition, LMU will crash if any rearview mirrors or any ingame video screens are active.

[Anna180]

Hi @Saabjock,

This shadow strobing/flickering in Le Mans Ultimate with Intel ARC GPUs is a known issue reported by multiple users. Since you’ve tried all drivers up to 32.0.101.7029, it seems driver-side fixes haven’t fully resolved it yet.

A few steps you can try as workarounds:

1. Lower shadow quality or disable certain shadow effects in-game.

2. Toggle hardware-accelerated rendering or ray tracing options if available.

3. Ensure game and GPU drivers are running the latest hotfix patches.

4. Report your captured video and logs to Intel ARC Support to help prioritize a fix.

Until Intel releases a targeted driver update, partial workarounds in the graphics settings are usually the most reliable approach.

[Saabjock]

I guess I...we LMU users, will all need to wait for a driver fix because everything you have proposed, I have already tried.

The problem extends to not being able to turn on in-game videos jumbotrons or rearview mirrors on actual cars.

That information ought to be enough to get the driver team pointed in the right direction.

This issue is as old as LMU itself and has been reported for months...not days or weeks.

Thanks for the response.

[Mike_Intel]

Hello Saabjock,

Thank you for the update.

For me to have this further investigated, please help provide the following details.

1. What is your game launcher?
2. Please share a screenshot of the game Graphics settings.

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[Saabjock]

I have tried both STEAM and SimHub for launching....no difference.

Here is what it looks like using the external playback camera.

Notice the strobing on every surface a shadow should be cast on.

https://www.youtube.com/watch?v=-p7GX4VTyZE

[Mike_Intel]

Hello Saabjock,

Thank you for the information provided.  

I will do further research on this matter and post the response on this thread once it is available.

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[Mike_Intel]

Hello Saabjock,

I hope this message finds you well.

I just want to update you that I tried to replicate this issue in our lab using the same configuration however, I wasn't able to replicate the issue.

Because of this, let me recommend the following:

• Update the BIOS ASRock | X570S PG Riptide to the latest.
• Install all pending windows update.
• Is the rebar enabled?

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[Saabjock]

Hello Michael....

This is a known issue for Intel users only, in the LMU forum.

As an Intel employee, I highly doubt you would be testing with an AMD CPU. Please respond, stating if you did. Thanks.

As to my configuration.... I already had the latest ASRock X570S PG Riptide BIOS before submitting the issue here.

That version number is P5.67. I am also using the latest Intel driver but have had the issue with every Intel driver used.

All chipset drivers...all firmware for all items and all drivers are the most recent for all hardware.

Rebar has always been on since the day in December 2022 when the card was purchased and installed.