Running Windows through SD Card or USB thumb drive
I tried this some 2 weeks ago on my retina 15" Mac. The usb I used was Kingston HyperX 128 gb, 3.0 . It ran WinToGo which is basically windows 8. I wanted to play Battlefield 3 but the result were very poor, I actually never managed to play multiplayer because servers kicked me for being AFK :D If you want to try some less demanding games it might work, but 32gb is not enough provided Windows alone would eat some 20-25 gb.