Game disconnected: client closed down connection. DURING GAME.

I can get in the graphics are nice but every so often (Every match so far) I shoot my rifle or someone else does my game freezes and crashes. I lose the points I am trying to make. I run the System stress test and it comes up with 0 FPS bad rating when I come back in but my graphics are smooth and happy, so 2 issues. The system test I could care less about but come on guys what do I go to do I played with my sound settings to try and fix it uploaded newest drivers the works.. I loved the Champaign but I really want to rule the Multi player as well.