Software works to reduce power when it is not needed.....doesn't change what's happening when you need and use that power. And EPU doesn't make a whole lotta difference nor do anything ya can't accomplish in the OD or BIOS by yaself. Best way to cool ya PC is to use proper cooling and component selection.
Don't skimp out and use small / inexpensive cases
Use more low speed fans rather than fewer hi speed fans
Don't skimp on PSU size, PSUs reach peak efficiency at 50% load.
Use an aftermarket CPU cooler if overclocking
Make sure all intakes have dust filters
Use spot cool type fans for problem areas
Have all fans respond to changes in CPU temperature via BIOS