I want to use 120mm fans but my pc has 80mm holes

[TechLaller]

I want to buy circle stay cool c-12 120mm fans but my cabinet only has 80mm fan holes. Any idea

 

[dorsal]

This isn't a very complicated answer, nor is it the best fix but... If you line up just one of the screw holes on the fan with one of the screw holes on the case you can usually get it to mount, but it will only screw into 1 hole. It could rattle or make extra noise, or may not fit at all depending on the case width.
I've done it to my own build with a smaller fan into a larger fan space.

 

[M0j0jojo]

I want to buy circle stay cool c-12 120mm fans but my cabinet only has 80mm fan holes. Any idea

Use Zipties, to tie the fan in place. I've done this with my CPU cooler fan, as I have a Scythe Ultra Kaze on my NH-D14 which doesnt fit LOL.

 

[TechLaller]

This isn't a very complicated answer, nor is it the best fix but... If you line up just one of the screw holes on the fan with one of the screw holes on the case you can usually get it to mount, but it will only screw into 1 hole. It could rattle or make extra noise, or may not fit at all depending on the case width.
I've done it to my own build with a smaller fan into a larger fan space.

Can I use zip ties? And isn't using just one screw going to make it unstable?

 

[dorsal]

This isn't a very complicated answer, nor is it the best fix but... If you line up just one of the screw holes on the fan with one of the screw holes on the case you can usually get it to mount, but it will only screw into 1 hole. It could rattle or make extra noise, or may not fit at all depending on the case width.
I've done it to my own build with a smaller fan into a larger fan space.

Can I use zip ties? And isn't using just one screw going to make it unstable?

Not really, once that screw is completely tightened the fan isnt going anywheere.