If someone wanted to spend an insane amount of money to make the ultimate gaming computer, they take take a high end server motherboard, load it with with 32 gb ram, dual CPUs, and multiple graphics cards, right?
Most of that would be a waste, of course and mostly for bragging purposes. But it would still be fundamentally the same as a PC?
To top this all off, only server OS's make use of nearly as much as all this hardware, so you would have to make sure the game plays on that OS.
Good project for rich kids with money to waste
With all of that power from the memory and CPU the bottleneck would be with the video card. Server motherboards usually only have one if any graphics card slots.
http://www.newegg.com/Product/Product.aspx?Item=N82E16813151162
PCI-E 16x -- 2 PCI -E 8x --1 PCI-X -- 1 PCI -- 1
Not bad. PCI 16x will support some pretty decent GPUs for quite awhile yet.
128 GB ram
2 x 32. ghz xeons
Ultimate multitasking computer.