Couple of things to try:
- Update to the latest dev build
- Open NVIDIA Control Panel > 3D Settings > Manage 3D Settings > Program Settings tab > find "Dolphin Emulator (dolphin.exe)" in the drop-down [or add it to the list] > Power Management Mode > set to "Prefer maximum performance"
-> Dolphin tends to do weird stuff to the GPU that a normal PC game doesn't, so your GPU may not be estimating the load properly and staying in a lower-power mode (or rapidly switching between low and high power mode)
-> Don't mess with any other settings here, Dolphin doesn't like enhancements being forced from the Driver
- Make sure you have the latest GPU driver isntalled
- Update to the latest dev build
- Open NVIDIA Control Panel > 3D Settings > Manage 3D Settings > Program Settings tab > find "Dolphin Emulator (dolphin.exe)" in the drop-down [or add it to the list] > Power Management Mode > set to "Prefer maximum performance"
-> Dolphin tends to do weird stuff to the GPU that a normal PC game doesn't, so your GPU may not be estimating the load properly and staying in a lower-power mode (or rapidly switching between low and high power mode)
-> Don't mess with any other settings here, Dolphin doesn't like enhancements being forced from the Driver
- Make sure you have the latest GPU driver isntalled