What are the rubber circles for on the back of my pc case? Should I just leave them like that if don't have a need for them? Or are they likely to let I'm dust into the motherboard?
Edit: thanks for all the replies, so just for water cooling I have no need for.
Only sort of, it still exists but it's a lot more compact now. And not super common as far as I know, like the other poster said here air cooling has come a long way. I've got a water cooled GTX 1080 Ti in my rig right now, but it's basically just a couple rubber tubes coming off the GPU leading to a little square radiator that I have a fan bolted to. It all sits inside the case (or, well, it's intended to... My case isn't quite large enough for everything I've got in it so I've got the radiator and fan a little bit jury-rigged to the front of my case right now. No biggie.)