I've searched, and found these solutions;
1 -
After running the game, go to task manager
Find GTA5.exe. Set priority to high.
Find GTAVLauncher.exe and all subprocess.exe and set them to the lowest priority.
2 -
To configure the compatibility mode for an application, just locate the installation directory and right click on the .exe, selecting Properties from the menu, Select the Compatibility tab, Set the compability mode for Windows 7 or 8. Start the game and enjoy!
