Applying new thermal paste on gpu

i watched some videos on it and ive done it before to a cpu but  what i question is do you put thermal compound on the black small squares you could say like a person does it in this video

https://www.youtube.com/watch?v=WxZ0ujOCzso

i have taken off the small things which i assume were the thermal compound before long ago and i was wondering as im gona reapply thermal compound on my gpu should i put it on the 'squares' also? or they are not needed and it will only destroy the gpu if i do

The video is NOT a good example of how to apply thermal paste. Unfortunately there are tons of youtube videos showing flawed methods of applying thermal paste. You only want thermal paste between the processor and the heat sink. I am pretty sure thermal paste which just connects to the thin air doesn’t do anything for you. 

 

my heatsink has a huge copper plate meaning yes if i would put thermal paste on the black square it would connect

all im asking is it safe to do it?