Question
Please tell me why "Optimize DaVinci Neural Engine" is displayed when starting up and what to do.
Answer
Optimize the DaVinci Neural Engine settings used in DaVinci Resolve according to the installed GPU/CPU. Displayed on first startup in 18.6.
Select <Optimize> and wait for a while.
Depending on the specs of your PC, it will take about 3 to 10 minutes.

This allows you to use DaVinci Resolve in a state optimized for the DaVinci Neural Engine.
However, if you have problems with the operation or want to disable DaVinci Neural Engine's optimization, you can disable it from the environment settings. [DaVinci Resolve] - [Preferences] - "System" tab - "Memory & GPU" - GPU configuration - uncheck the target item and restart DaVinci Resolve.