Fopnu is not entirely compatible with the software 'Stardock Windowblinds'. It causes very very high GPU usage.

The fix; in Windowblinds configuration goto the 'Per application' settings, add fopnu.exe and under 'Advanced Settings' check 'Only skin this applications title bar'.

You will need to restart Fopnu for it to take effect.

It is also a theory that this may apply to other (more recent) software from the same vendor.

Thank you.