ParkControl

This program is by the excellent folks behind Process Lasso. It's essentially for very high performance at the cost of some additional electricity. CPU parking is by and large a good thing and saves on electricity, but when even small delays are painful, this can help.

Big thanks to Midas for explaining this to me.

Requires admin rights and it's a pretty specific use case, meaning I don't see a lot of portable apps users with high end processor needs. Native portability is untested but could probably be enabled via the command-line powercfg.exe utility.