If you plan on running ESXi, then your first problem is finding a motherboard that's supported or at least known to work with it. With Hyper-V, any system that runs Windows Server 2008 will work fine. There are lots of server motherboards that have 8 memory slots. Newegg have 32: http://www.newegg.com/Product/Prod [...] chInDesc=. They have a few with even more memory slots if need be.
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