what makes an emu faster than the other ?

[VIRGIN KLM]

lol virgin, he was talking about internal overclock (like faster processing speed in the emulator or slower one ) I don't understand how internal downclocking in ppsspp works ahah..

This is what I was talking about virtual or not.
PSP games are programmed (most of them) like PC games, they have a FPS cap but the speed of the game remains the same regardless of higher or lower clocks or FPS UNLESS the CPU reaches a state that cannot keep up anymore and you notice effective slowdown.
NDS on the opposite side, FPS and clocks (virtual or physical) are binded together. Higher clocks = more FPS = higher speed than normal, lower clocks = less FPS = lower speed than normal. There have been attempts and tricks to overclock NDS by modifying the kernel or with a frequency oscillator but the result is exactly the same since the games are programmed to react this way.