Yeah. But not as bad as people will claim. But you'll at least see a more stable frame rate. If you OC, you'll also get better FPS.
And, if you're playing on a 60Hz monitor, anything over 60FPS can cause screen tearing. Which is why I usually turn on VSYNC. But if you want over 60 FPS, 660 SLI can and will provide that, even with your phenom 965. If you want to upgrade CPUs, I would recommend an i5. But AMD SteamRoller CPUs are coming Q1 of next year. So if you can hold off... You'll get better performance for your $$$