Speaking from experience: there’s almost no measurable perf benefit from disabling ondemand governor on Pi3 or other low end boards. I use Pi3 as a cortex a53 benchmark baseline, and I no longer bother controlling the clock.
This does not hold on higher end boards though. E.g. NVIDIA TX1 or 2 is considerably faster if you force max clock.
Unfortunately I don't see any graph as to how much more performance was squeezed out of it, and neither any data of the temperature increased, although in comments I can see people providing some answers with their heatsink and fan set ups. I would be curious to see if this has any improvement for applications such as games in RetroPie.
Since older rpi models can run NES games, I guess the rpi3 is more powerful than necessary. And if the game you’re playing is running smoothly, why bother? With the consoles, there are no graphics settings.
The Dolphin Emulator has been posted on HN before it emulates both the GameCube and the Wii. That is the one emulator that impresses me the most... You can play online with other Wii players if you extract some info from your regular Wii, aka make your Wii immortal to a degree by digitizing it...
There is a Wii U emulator kicking around. And a few 3DS emulators -- which is a hoot, given that the 3DS is still a living, supported system getting new retail game releases weekly.
There are several emulators available. For example most 2D PSX games work fine. However, most PSP games are unusable due to glitches; N64 games aren't really playable with default settings either.
This does not hold on higher end boards though. E.g. NVIDIA TX1 or 2 is considerably faster if you force max clock.