You should also make sure you don't have any malware or viruses that might be affecting your bandwidth such as a "Downloader" virus or somethingl like that. If your computer is clean and the issue comes back, check in another game or make a speedtes…
The main thing that seems to increase performance right now is High clock. People with 4GHZ or more seem to get better performance, because of how to game was designed. So the best bang for the buck would be to OC your CPU.