Fever_Discordia: Yeah, Slave Zero is on the Tommo list
Mobygames says 'Playmates' for Powerslave, which sounds dodgy and 'R' rated!
I'm pretty sure the jumper is on 'Slave' and not 'Master' - there's 2 extra pins on the left that aren't used (I think they're there to retain the jumper so you don't loose it if you don't want it on any of the settings) try counting them from the right...
I have to agree with adambiser - direction doesn't seem to matter as it's in the middle.
That said, the hint could be purposely misleading, so I wouldn't be surprised if it's the Tommo game.