FPS Problem while gaming on Acer Nitro AN515-54 NH.Q59SN.005

Jack223

As i mentioned on the title, something wrong with my Acer Nitro 5 NH.Q59SN.005.
When i play a game like CSGO the FPS always fluctuate like crazy amount,from smooth as butter to look like **** (since it got 144hz refresh rate).
The CPU temp is around 70*C , the GPU around 65*C on fully loaded so no temp throttling on my laptop.
I already made sure to charge the laptop to 100% and always keep the charger on.
On windows,Nitrosense,nvidia control panel, intel hd graphic menu, etc everything already set to maximize the performance yet the problem still occure.
I even reinstall the nvidia and intel's driver with DDU and download the driver straight from the website and install yet no solution.

So i need a serious help on how to solve this FPS problem guys

Here's a video on youtube of how it looks like when playing

https://www.youtube.com/watch?v=iG_4pi0aCSs

Here's the laptop spec : 
Intel I7-9750h
GTX 1650
16GB of RAM (Upgraded)
256GB SSD
500GB HDD (Upgraded)