If it is possible to load intel_pstate on your platform and driver will initialize and supports a CPU model, then in some cases intel_pstate cpufreq driver can work better due to its algorithms. Intel_pstate can give you access to "turbo" P-states (that acpi-cpufreq driver sometimes does not support) and in case of using "powersave" governor it can save you a little bit more power than with ot...