I know that feel. My Model B was the first batch of them 256mb ram shared with the GPU. Playing any SNES game with an FX chip is a no go for me here.

Pi Zero only has 512mb ram shared with the gpu, It doesn't even have network access and uses a single core 32bit cpu. I can overclock my pi model B to around there and some games are still simply unplayable for me.

what did you do with your pi model B? mines just sitting in a cupboard, I had it hooked up at one stage to a PS3 PlayTV dual tv-tuner that you connect to your playstation3 to give you live tv channels and PVR functions, but works perfectly out of the box with the Pi.... it lets you record and watch live TV on any device in the house (mobile phones, tablets, other tvs, computers, etc) all via a nice web interface or app

but i kinda just gave up on that when i stopped watching tv... now I don't know what to even do with it, I can't even find a place online to buy a new case for it. I was going to re-purpose it if I could find a case and 2 usb nes controllers and pass it along to a family member as a 'nes mini' ... but no cases for sale here or on eBay that I can find