I tend to have the same issue with FPS loss. I ran SPM while running around through thick grass.

Image has my specs. My VRAM seems fine so no idea why I keep getting these huge FPS spikes down to 2-4 fps. I also know the temp on the SPM is incorrect as my system temp gauge has much lower temps.
[MEMORY]
ExpandSystemMemoryX64=true
ReduceSystemMemoryUsage=true
DisableDriverMemoryManager=false
DisablePreloadToVRAM=false
ReservedMemorySizeMb=1024
EnableUnsafeMemoryHacks=false
[FIX]
FixPhysics=true
[WINDOW]
ForceBorderless=false
ForceBorderlessFullscreen=false
[ENGINE]
ForceAnisotropicFiltering=true
MaxAnisotropy=16
EnableVSync=false
AddDisplaySuperSamplingResolutions=false
[LIMITER]
WaitBusyRenderer=false
EnableFPSLimit=true
FPSLimit=60.0
Anyhow wish I could be of more help. Nvidia driver is 326.41. I have a lot of HR textures, tons of grass mods, and HG ENB settings. My ini settings are pretty vanilla though - just the ones you need for ENBs.
EDIT: In case it is of any interest I did the exact same save and run I did before - didn't change anything except use the 201 dll and 201 enbhost file.
