This is a weird case. When I tested a Genesis 2 power adapter, the cartridge I'd tried worked yet CD games seemed a little flaky.

Now that I have a real CDX one things are different. With the cartridge side, the TMSS screen appears than goes blank and doesn't start up the cart. As for the CD side, the BIOS screen loads fine but I don't at the moment have a controller to get in-game with.

I suppose my Mega Master converter could factor in. Maybe shorted out the slot or bent its pins? No clue. It wasn't removed when powered or anything stupid like that.

Though I've never found any proof whether the X'eye supports SMS mode. (My guess is that's because Sega only released Power Base Converter 2 in regions X'eye wasn't, so nobody bothered to test.)