What version of the NVIDIA drivers are you two using?
The latest R331 drivers.
I am also having identical issues with the same R331 Nvidia Drivers.
From what I've noticed since the beta is that CPU will kick up from around 80% usage (little to no stuttering) to 96-100% (heart of the stuttering and frame drop). This will rev back down to the 80% (end of stuttering burst). This occurs about every 30 seconds, making vehicles and most ground movement unplayable.
Also, from what I can tell is it happens most commonly for me during and after "levolution" events. It almost seems like an issue with particle effects (dust, explosion debris etc.)
I have changed graphics settings from low to Ultra High and have roughly the same framerate issue.
Nvidia 560Ti
AMD Phenom II Black 955
8GB Ram
180GB SSD
Dual Monitors @ 1920x1080
