Run Afterburner and check your GPU usage. If you are running at 99% GPU usage in that particular game, then you have no bottleneck. If you are running at less than 99% GPU usage, particularly if its closer to 50% or less in that particular game, then you have a CPU bottleneck.
Yes, I installed afterburner and sometimes it dropped sharply below 50 percent in the benchmark's. So to solve this problem I install a new processor right? like 3.0 ghz?