I got to thinking the other day (I know, I know, it was a rare occurrance) about multi-denomination slot machines and their payoff rates. So at the risk of further revealing my lack of knowledge, here goes.

It seems that I see more and more slot machines where you can choose to play for 3 or 4 different denominations (maybe 5, 10, or 25 cents). Conventional wisdom says that generally, the higher the denomination, the lower the casino hold rate. It makes sense - the casino would have to keep less of a $1 bet than a 5 cent bet to make money. And you don't see any "98.8% payback" signs posted over the penny machines. I would guess that the hold percentage is determined by the random number generator.

So - if I play a multi-denomination machine is the casino hold percentage the same regardless of which denomination I select? And if so, is it set at the highest advantage for the house? Or is the circuitry smart enough to adjust the hold rate based on the denomination selected?

Any of you insiders know how this works?