Pop Ups

I need help. There is this stupid pop up on my computer that is really bugging me it pops up when I play my games and so on. I don't know how it is doing it i scan my computer and it didn't find andything (Full scan). It pops up in my google Chrome and shows a website called Plarium.com and it says join our game. and it happend to me 4 times already and I am trying to figure out why its doing this and where it is. I am using windows 7 Home Premium and yes i actually bought this from the store not download it illegally so please can anybody help me with this dam Pop Up.

I had something similar, and i just went in to control panel and saw i had some new app installed, and i just uninstalled it and cleared cache and checked if there are any new extensions 

I did and nothing comes up like no new extension or cache.

use malwarebytes and ad-aware to scan your computer. I find that ad-aware does a better job at finding adware than MBytes.

I am also annoying with those kind of pop ups however i don't have idea on how to get rid of them ,in fact even i am working in IT company  at http://www.mpy.fi/yritysasiakkaat i did not yet solve this kind of problem.