Whats is the Amperage rating on your power source? I think that's the same dealer i got mine from and it runs on 5V just fine.
+5V and 2.5A. I've also tried batteries (4AA rechargeable) and a psone adapter, since the page says it's rated for 12V. Both adapters are DC and I did check to see which part of the adapters was ground.
The AMS117 chip receives the 5 volts just fine and outputs the 3.3 volts that it is supposed to. So whatever problem there is, it's past that part. Maybe I just got a dud.
Edit: NVM. I dunno why it's working now but it is. Second video channel doesn't work but it's not like I really NEED two. Hooked it up to some batteries one last time and put my ear close (random) to see if I could hear that electronic 'whine' and I could... so then I connected my psone to it and bam, menu screen. I think maybe the thin ribbon cable inside was a little loose, as I had played with it previously to see if it was a bad connection, but before it didn't work. There are three spots on the side for switches, I'll see what those do later.
Edit2: Video only works if it comes on roughly at the same time the screen does, which was probably my problem before. If I turn on the screen, wait, then plug in the yellow, nothing. No blue screen to search for the video.
Also getting some interference, probably from the power line being so close to the composite without shielding. And blues have some vertical lines in them. So wave race 64 looks horrible.