Yesterday my CPU cooler was making a lot of noise so I took it to the service. They replaced it with another one and told me they put some kind of paste there, so that it works better.
It works fine now, but it constantly (while it's on all the time) makes a very very low hissing noise around that same area. I'm not sure if that's just how this new CPU cooler sounds or if it's from the paste of what. It's not getting overheated or anything, everything runs smoothly. Do you know what this could be?