laptop lag

i have my laptop asus x556u.. its lagging for time to time i already updated my graphics cards.. some times my cpu goes down and gpu goes up that is the time the lagging start and also may mouse pointer also lagging for that moment.. when it goes to normal the cpu goes up and the gpu goes down...

I got the ASUS F550VX back in September and I've been using it for video editing, playing Sims 4 and casual internet browsing Specs: Intel Core i7-6700HQ 2.6GHz, up to 3.5GHz RAM: 8GB, NVIDIA Geforce GTX 950M. Windows 10 I've also got an SSD of 128GB and a 1TB HDD, both are only half filled up...