Can't Get On Wifi With One Computer But Works With Laptop

As title says, my wifi works fine on my laptop but won't work on my computer. This hasn't been an issue previously but I moved house and now can't get on. I've tried two different dongles, changing the channel my router goes on and a new router. The computer connects and says it has internet access but then whenever I try and load a webpage it just keeps loading and never actually brings up the page. Also tried a few ipconfig (flushdns, release and renew) through cmd as I was instructed to by a friend - but now can't think of anything else. Also, it has three out of 5 bars of strength but sometimes when I switch the computer on it doesn't even detect the network at all.