This is why you find slower clock speed Intel CPU's outperforming higher clock speed AMD CPU's.Emulators must be coded to interpret different architectures and translate them to x86/x64 code in order to trick a PC into thinking it's something else. It also depends on how the emulator is coded and optimized, whether or not hacks are used to give a boost in speed, etc. The whole MHz Myth really bugs me sometimes; people need to realize that higher clock speeds don't always mean faster performance. A Core i7 2.2 GHz outperforms a Pentium IV at 3.0 GHz easily, not because of the speed, but the instructions, the no. of MIPS and floating-point operations or FLOPS. The 3DS could easily handle Snes and maybe even Playstation, but how well that would run is anyone's guess. But again, it all boils down to how efficiently the emulator code is written and executed.
Anyway, as far as the original purpose of this topic goes...