Is identical hardware required?

[Hito]

The only hardware I can think of that is prefered to be identical, is if you have multiple graphic cards run in SLI. Other then that, like said before, it is a bit easier to manage if all clients have similar performance/latency. But it is far from required to run identical systems.

I don't plan on doing anything exotic like SLI. I don't think WoW could make good use of it anyway. I basically plan on following Bradster's approach with some hardware differences.

Since the hardware doesn't have to be identical, I'll shop around for something like the gigabyte setup I just upgraded from. I know I plan on sticking with gigabyte mobos, OCZ memory and power supplies, and NVIDIA video cards. I'm getting too lazy to learn a new control panel, so I'm sticking with what I know.

Since I'm putting everything in a rack, I was considering a large-ish liquid cooling system to cool all five computers. All those fans could get loud and since I happen to have a 50 gallon fishtank I-'m not using, it sounds workable.

Sorry for the ramble. Thanks for the quick answers.