I have a two year old ASUS AM3 MB with a AMD quad core 3.6ghz BE CPU. I have a high powered nVidia GTX295 GPU.
I continually experience delays and poor FPS in games, including WoW. I understand that the CPU can be a bottleneck with WoW. I want to significantly improve that performance. I intend to keep the GPU.
Would like to know what the best performance AMD CPU and MB combo would be (including memory) that works best with my GPU, to resolve this issue.
Do I need to leave AMD behind and shift to Intel to properly take advantage of my GPU's capabilities and improve overall performance?
First off, I don't know what CPU you think you have, but unless you've overclocked it, there is no 3.6 GHz AM3 quad core. I assume you mean you have X4 965 (or 955). Second, you cannot have a two year old AM3 CPU or motherboard. The sockets only been out since February 2009, so it's at most 9 months.
But that's really besides the point. The real point is that if you have what you say you have (on overclocked AM3 X4 at 3.6 GHz), there should be no bottleneck. That would be on par with the fastest CPUs out there. Besides, no current CPU (i.e. AM3, LGA1156, LGA1366, late LGA775 multi-core units) would be the bottleneck for gaming. I'm betting that (again, if you have what you think you have), there's something else causing it.
Possible issues would be that you actually have an AM2/AM2+ CPU that's an older model, which could cause a bottleneck. Or you could be running on very little RAM or very slow RAM. To really tell what could be causing the slow-down, we need to know all your components. What EXACT motherboard and CPU? What make and model RAM? What HDD and PSU? What OS are you using?
EDIT: Sorry if that comes off with me sounding like an a$$, but frankly exaggerations and guessing don't help get you answers. To provide the best help, we need to know exactly what we're dealing with.