Found it. (Using Google Search in AI mode). The answer is as follows; and it worked!
“This is a known issue that often occurs on systems with two graphics units – the integrated GPU of the Intel Core Ultra 7 (iGPU) and the dedicated NVIDIA RTX 4060 Ti – typically after updates. Lightroom “loses” the assignment and incorrectly routes AI computations to the CPU or the slower Intel graphics instead of using the GeForce card’s tensor cores.
1. Force the RTX 4060 Ti in the Windows settings
Windows often tries to decide dynamically which GPU to use. You can override this manually:
- Open the Windows settings (Windows key + I).
- Go to System → Display → Graphics (or simply search for “Graphics settings”).
- Click Browse and select Lightroom’s executable file (usually located at C:\Program Files\Adobe\Adobe Lightroom Classic\Lightroom.exe).
- Once Lightroom appears in the list, click on it, choose Options, and set the mode to High performance (make sure your NVIDIA GeForce RTX 4060 Ti is listed there).
- Restart Lightroom.
2. Delete the corrupted Camera Raw GPU cache (!)
Lightroom or driver updates often corrupt the configuration file, causing Lightroom to block the GPU. Deleting it forces Lightroom to perform a clean hardware rescan:
- Close Lightroom completely.
- Press Windows key + R, type %appdata%, and press Enter.
- Navigate to: Adobe → CameraRaw.
- Look for the folder named GPU and delete it entirely (or rename it to GPU.old).
- Restart Lightroom. The program will now freshly scan your hardware and recreate the folder without errors.
3. Use the NVIDIA Studio Driver instead of the Game Ready Driver”
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