client/server synchronization should not affect fps, whether it does in this game or not I can't say. Connection speed and latency determine where and when you see characters in relation to where they actually are on their own screens, how long it takes for you and others to perform actions(client side), have those actions performed(server side), and lastly see the results of the actions performed (client side once again). Again, your computer doesn't normally wait for this information to draw frames, it should be draw them as fast as it can regardless of the information it's sending/receiving to/from the server