The most powerful servers in the World!
Which is the best server to run Exchange Server? It's not an easy question, but if the deciding factor is performance, then MAPI Messaging Benchmark 3 (MMB3) is the right measure for you.
MMB3 is the benchmarking standard for measuring the performance and scalability of computers running Exchange Server 2003 and basically it measures the maximum number of concurrent users a server can handle.
Hardware vendors are constantly trying to set a new MMB3 record, that's why the leader changes over time. Microsoft publishes regularly the results on the page Performance Benchmarks for Computers Running Exchange Server 2003.
There are 2 main categories: single server and cluster. There a couple of rules that the servers must meet, namely they must run during a 4-hour steady state period. Results should be interpreted as a benchmark for messaging throughput and should not be confused with deployment recommendations.
Presently this is the current list:
Single server
Cluster