Game uses the wrong graphics processor

On systems with several graphics processors, an app may choose a different GPU than expected.

Stop if there is smoke, a burning smell or severe graphics corruption under load. Avoid speculative stress tests, overclocking or power-supply work.

First check that the device actually has several graphics processors. Using power-saving graphics for ordinary laptop tasks is normal.
Open Settings → System → Display → Graphics. Select the game and, if available, choose the appropriate high-performance GPU under Options.
Save the selection and restart the game. Compare performance; power use and fan noise may increase.
Do not disable integrated graphics in Device Manager or BIOS speculatively. If unclear, record the model and game for manufacturer support.

Test after each step and stop when the issue is solved. Checkmarks are not permanently saved.