Change LCD density value?

Anybody tried to change LCD density in build.prop file? My G4 F500S unable to boot normally after I changed the value to 480. My phone is able to pass the LG logo screen, sometimes it will display the apps optimization in progress.. when optimization done, it display something like system ui problem (can't see clearly as it rebooted in very short time)... Still finding a solution to fix the problem now :(