Sadly above poster is right. Even if you upgrade your CPU, it will never see 100% utilization for WoW. In fact, your FPS is heavily impacted by how many addons you run. As you probably know, if you run no extra addons, your performance skyrockets. Once you start adding mods that require communicating via hidden channels or with the server, it starts to slow down quite a bit. Recount etc severely impact FPS, especially in large environments like raids. I have a 2600k @ 4.8, 16gb 2133, and a 5870, and my FPS is great. Upgrading the video card will do nothing to improve upon it. If you already have low mods, then your bottleneck is without a doubt your CPU, even though it is advanced technology compared to when the game was released. The game just doesn't utilize it well as you can see by checking your CPU usage when your FPS drops. You can go down to ~20fps and your CPU will probably be at like 35% usage.