How can I get rid of all this noise I want to render a scene where light shines through a ball with holes so I get a dot-pattern similar to a disco ball. (see pictures) The problem I have at the moment is that my render is very noise and I just can't find a way to get rid of it. I tried quite a lot of different "solutions" that are supposed to fix it but with no success. Using more samples also doesn't really help. (I'm using 500 samples) I hope someone can help me with it.

I uploaded the pictures here: http://imgur.com/a/CwUgR
and the .blend file here: http://koncake.bplaced.net/blender/wasserglaubich.zip

(I couldn't use blend-exchange because the file was to big)
500 samples is really a small number for most scenes. Turn that up to 1500 or 2000 and see how it looks then. There are ways to make more samples render faster, but the only way to really get rid of noise is more samples.

The issue of noise in Cycles has already been covered well in other answers, so I won't duplicate that here. Search the site, and you will find all the information we have to offer.

This answer is the best place to start: How to avoid noisy renders in Cycles?