i have a 4 gb nvidia 940 mx gui but when i play any game the screen gets lag and it get solved as soon as i connect the charge

[ajishanil50]

I'm playing need for speed most wanted and sometimes when I run the game the laptop screen experience some lag, but the lag gets solved and the game works perfectly fine as soon as I connect the charger.

 

[popatim]

Many laptops underclock or reduce the number of 'cores' the gpu can use (or both) when running on battery.
This may be normal and should be mentioned in your users manual.