I recently bought an Nvidia Geforce GTX 260 and it is not giving the performance I anticipated at my 1920x1080 resoltuion. I have an AMD Athlon 64 X2 5000+ running at 2.6ghz, whereas most benchmarks I see have processors running above 3.0ghz, most of them even quad core. It's the only thing I can think of to be a bottleneck , as I have 4gb of ram and again the GTX 260 (properly powered). I just want to check any other possibilities before buying a new processor.