Having said what I have said earlier... About building my own machine... You do understand that the major difference between Windows PC and a Mac is that a Mac is not built by any Dick, Tom or Harry in their bedroom? If it was, you would have just another system that would work averagely on some machines, and just terribly on all the rest.
As for gaming... I do agree, Macs are not built for that, not even the Mac Pros...
So, if you want a gaming machine... Build a PC.
A Mac is not built by any Dick, it's built by many tiny Asian people in a Foxconn plant along with all of the other name brand laptops. PCs and Macs are no different in that regard, contrary to whatever you may believe. I have built many a PC before and not only is it not hard, but it's also not hard to do and to keep and maintain a custom built PC. Not only that, but said custom built PC runs far better than any name brand PC. Have you ever used such a system? Because it sounds like you haven't and thusly don't know what the hell you're talking about. PCs and Macs are both good for 80% of all practical applications. To make such a comparison in the fashion that you have is fanboy-ish and ignorant.
The question is... who is going to support those masses of "OS X monsters" ? Apple sure as heck isn't... they haven't certified the hardware, so they won't support their software on it. So I hope you have masses of staff to support your computers when problems develop. Including software issues...
Okay, so my comment rolled with the hypothetical "if Apple Licensed OS X" in which case you know that AMD, NVIDIA, and just about every motherboard manufacturer would likely offer drivers, right? When Apple announced the Intel transition, many manufacturers openly stated that they'd support OS X on standard hardware if Apple let them. As for who would support those machines; I have seven different Apple certifications; I think I can handle it to start. Though Apple is never going to license OS X so it's a moot hypothetical anyway.