only advice is to make it a 64 bit OS, so you can add more than 4 gig of ram later on if needed. Domino needs to be on 64 bit as it needs more RAM in many cases as mention by RIM a few years ago in a seminar I attended. Exchange might be able to get away with 32 bit but why chance it when everything seems to need more resources as time goes on.
I had to fall
To lose it all
But in the end
It doesn't even matter
running mine on 64-bit 2008 R2, although BES installs as 32 bit, and 2 CPU and 4 GB RAM. Monitoring the VM with vCenter Operations and I'm not overloading the VM at all. Running about 1500 BBs divided between 2 BES servers with HA running. All four servers are VM.
4 - BES Servers (5.0.3),
~1500 BB Users, and a headache.
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