First things first. Does this problem occur when you are hardwired? Connected via ethernet? If so, then something is interfering with your signal. If not, then pursue the course of action you are. Here Drivers - Linux Wireless you can see the realtek devices and drivers that are supported for Linux. Please run lspci to show more info about your realtek card. Seriously though, start with what I said at the beginning. Does this problem only exist on wireless? How close are you to the router? What's around the router? What is between you and the router? What are your walls made of? You'd be surprised as to how often these get overlooked and make all the difference.