Whenever my GTS 250 enters its power save mode via Powermizer, downscaling its frequencies, my audio stutters. This affects both my onboard audio and my Audigy Soundblaster 2 ZS. Changing Windows power save mode options such as PCI-E link state power management or Power Management Mode in the nVidia control panel have no effect on this issue. Replacing the power supply had no effect on this issue. The BIOS is the latest version, and I have the latest motherboard chipset and graphics drivers installed. I do not overclock.
I started to see this issue after I upgraded my rig from its Socket 939 board to a Socket 1156 board with a Core i5-750 while simultaneously upgrading from Vista to 7.