@asteroid @raccoon they have the computational power slightly above a potato, and will never run x86 software ever except some dosbox for very light games like commander keen.
They do however come with ports of games like doom, quake, cave story, and more.
And run indeed psx, snes etc full speed (this one and my new one at least) including Tekken 3 and such. Due to great optimization.
I have even seen people say some n64, PSP and ds games run good too, so with other firmware project diva