See that question in the header? The question that you see asked around here on a daily basis, and then some?? The question that absolutely should NEVER, EVER, EVER NEED TO BE ASKED?!?
Well, here's my proposal to rid us of this highly unnecassery hurdle once and for all:

Make the forum sign up template include two pulldown menus, with the computer type (PC or Mac) in the first one and selecting your system version in the second one - and these are mandatory for all forum members, new & old (oh yes, you oldies are just as bad with this one!). This will then subsequently be a part of your basic member display and this question, that should be long extinct, finally vanishes for good.
Never finish what you can't start!
BBox 2020 UltraPak, Mac Pro Intel, OSX 10.6.8, 800x600 (TV VGA)