From my experience (and that of many others) it's best just not to combine xanax and alcohol at all. It can very easily lead to total memory loss and stupid decisions. Will 1mg of xanax and 1-2 beers make you black out? Probably not, but is that the only xanax you have and are those the only beers in your fridge? Because if not, then you could end up getting yourself deep into trouble before you even realize it.