The datacenter move definitely should not cause graphics related stuttering. Could try updating or rolling back your GPU driver, and maybe even a clean install using DDU to wipe out any traces of old drivers that might be causing a conflict. It seems weird if it wasn't happening at all before the server move...Maybe your card is overheating and throttling performance? Try grabbing something that will monitor your temps (for example: HWmonitor. Lots of other options, though). Are you having performance issues in any other games?