Hi everyone!

I'm Graham from New Zealand and I'm just getting all set-up for some retro gaming. I imported a model 1 Genesis with the High Definition Graphics logo across the top (it seems a non-TMSS model as there's no licensed by screen) and a pile of games. Only some don't boot :/

Thinking maybe I had a dud console, or rather, a picky console, I got another one. Same model. Again it plays some games but not others. How odd!

I was wondering if anyone might have any ideas?

These won't play:

Sonic & Knuckles
Super Street Fighter II
Gunstar Heroes
Aladdin
Toy Story
Lion King
6-Pak
Toejam & Earl Panic on Funkotron
Earthworm Jim
Wonder Boy In Monster World

These will play:

Sonic 1
Sonic 2
Sonic 3
Street Fighter II Special Champion Edition
Mortal Kombat II
The Ren & Stimpy Show Presents: Stimpy's Invention
Castlevania Bloodlines
Road Rash 3
Desert Strike
Jungle Strike
Urban Strike
Beyond Oasis
Ghouls 'n Ghosts
NBA Jam T.E
Shining Force
Alex Kidd In The Enchanged Castle
Comix Zone

I've tested all games with both consoles, and the same ones boot and don't boot on both. I know some of the sellers played the games before sending them, so I doubt it's the games. The ones that don't boot, the screen is just black, and there's no sound (checked regular AV out at the back + headphones jack)

Any thoughts would be very interesting. Thanks!!