My game keeps freezing in-game

So I used to have a computer that wasn't very good, but it ran league perfectly fine. I needed to get a new computer so I got the HP probook 450 which was said to be good. When I started playing after I downloaded league I had these screen freezes, like my screen would just freeze for 3-5 seconds and then go back to normal. I tried repairing my league client but that doesn't seem to work either. Does my computer have a manufacturing defect or is it the league client. Does anyone else have the same problem as me?

Here is the link to my laptop: http://www8.hp.com/ca/en/products/laptops/product-detail.html?oid=7834555#!tab=specs