Alienware maybe, that was a bit before most of the other OEMs had gaming line-ups. But it wouldn't have been cheap and people would try to get as much as possible out of them. Everything else would have been semi-custom.
If you want that class of computer, no reason you can't find an LGA2011 Xeon. Though still not certain that is worth doing unless the price is really good at this point.
AMD CPUs have never been cheaper than they are right now for the performance. And it gets you into a fully upgradeable platform.