Hi, I'm just buying a US N64 as bit of an impulse. I believe it comes with the stepdown (I'm in the UK) but if it doesn't, can I just buy a UK power supply for the N64? I'm assuming I can..
Yes, sticking a UK PSU in to a US N64 works. I couldn't be bothered to use my step-down converter and deal with yet another plug, so I just pulled the PSU out of the back of my UK N64 and stuck it in to my US one - same with the video connector. It all worked fine.
