I recently got myself another Sega Genesis model 2. This one came with a sony chip so I can mod it. The only problem is that the system does not work. When I originally got it the cartridge slot was really dirty. It had pencil shavings shoved down it somehow. I was able to get them out by blowing through a straw, and vacuuming them out. The only problem is that the cartridge slot still doesn't work! When I turn it on, I get perfect audio, but the picture is completely garbled and screwed up.

I noticed this Sega Genesis is a little different from my other ones.

My working Sega Genesis model 2, Sega Genesis model 1, and JVC X eye all have cartridge slots that look like this:
http://i52.tinypic.com/2m3jygy.jpg

This non-working Sega Genesis has a cartridge slot that looks like this:
http://i53.tinypic.com/292b51l.jpg
http://i51.tinypic.com/v6pun9.jpg

Please somebody help me out! I really want to see this thing work.