CS Go Gets <30 FPS in Alienware M17x (i7 4800, 16 Gigs of Ram)

[Rock$tar]

Hey Guys,

My Rig:

Alienware M17x R4, i7 4800, 16Gigs of Ram, Nvidia GTX 770 Card.

I run in 120 hz refresh rate. My Problem is that game fps drops ot 30 FPs for 3-4 Secs and again gains 120-180 FPS. It drops every 10-30 Secs for 4 Secs and gets back normal again. I saw in youtube and tried several commands but nothing helped me.. can you guys please suggest me soemthing?