Just recently, FPS sudden drop

[Musicazzz]

Hi Technical Support,

I need help here. Lately, since 2 weeks ago, my FPS in game drops quite frequently from 60 to around 20-30 fps for 1 second, then back to 60 fps again.

It happens everywhere, but if i go to instance raid, it happens more often.
If i play full screen instead of borderless window, the fps drop doesn't occur as often.

GPU: NVIDIA 1080 TI (this is more than enough to play this game)
Processor: more than enough to play this game

I have recently (around 2 weeks ago) updated my NVIDIA driver.
I tried to roll back, but fps drop still occur.

Please help.