CPUFreq vs. P-State CPU Scaling Governor Tests On Various Vulkan/OpenGL Games
Under Metro Last Light Redux was also only minor shifts in performance with the exception of CPUFreq powersave.
Tomb Raider was crashing during some of the test runs, but for the runs that were recorded, P-State powersave was on par with CPUFreq performance.
The ET: Legacy performance was unchanged except when using CPUFreq powersave.
Tesseract is a game that does tend to be impacted much more by changes in the CPU scaling driver/governor than other games. With the performance governor, P-State and CPUFreq do the best but again with any of the configurations on modest hardware you would still have playable frame-rates.