Axiom Home Page Forums General Discussion The Water Cooler WIndows Server Hardware Recommendations

8 gig should do well to start. Get the biggest sticks you can, so you have room to add more later (i.e. don't get 8x 1GB sticks and fill up the board). I'm guessing you're looking at a single CPU board? If you're going with dual CPUs, you will need an equal amount of RAM local to each.

I don't know if you get fault tolerance in the free ESXi package.