I have the following rig:

Phenom II x3 710
3Gb ddr2 1033mhz
GTX 560 Ti @ 1000 GPU

And when im playing in DX11, i get around 40 fps and gpu load 99% but suddenly... the fps drops to 25fps and the gpu load drops to 60%, so im thinking something its limiting the VGA. It's that true ? I have the CPU at stock speed 2.6ghz.

THANKS!

The Phenom X3 clearly bottlenecks your GPU, need a quad core at least.

Dude........ definitely a bottleneck, 4 cores at 2.6..... i have a 4 core at 4.5 and GPU drops to 80% at times. Either OC that baby, or get a new one. You can get a AMD quad core for around $100.

Thanks guys.

Im going to OC it. I didnt do overclock because the lack of my power suply, but tomorrow a friend of mine its going yo borrow me a thermaltake 650w only for VGA so im going to OC the cpu. I only can go for 3.4ghz with stock cooler but, i think it gonna make some difference at least. Thanks, I thiking to go for a i5 2500k...

nVidia Drivers don't know about triple-core CPU's only dual-quad-hexa core CPU's... And that's true - so your x3 CPU is as just the same Phenom II X2 at the same clock. Switch to Quadcore AMD cpu, or if you have a lot of $$$ to Intel Socket 1155 platform, like core i5 2500k running @ 4.5ghz