ok... my megadrive knowledge is a bit rusty... let's see...

your sonic3 cartridge issit megadrive or genesis version?

I vaguely recall certain games can't be played on my megadrive also... but that was what? almost 16 years ago?

let's see... save game feature, I remember i can play games like Romance of 3 kingdom, Phantasy Star series, Shining Force series all without problem.

so it could be a string of bad luck for u thou... 2 bad cartridge in a row try to look for another megadrive if see it can boot or not.

it could be a PAL console, as only the American's are calling it Genesis while the rest of the world is known as Mega Drive

how much u spend just for sonic3 already?