Perhaps the most telling part of AnandTech's review of the Calxeda Boston Viridis server was the statement that "It's a Cluster, Not a Server" as that paints a different picture of the appliance in many tech's heads.  When you first open the chassis you are greeted by 24 2.5” SATA drive bays and a very non-standard looking motherboard full of PCIe slots, each of which can hold a EnergyCard which consists of four quad-core ARM SoCs, each with one DIMM slot and 4 SATA ports with the theoretical limit being 4096 nodes interconnected by physical, distributed layer-2 switches not virtualized switches which use CPU cycles.  Check out the results of AnandTech's virtual machine testing and a deeper look at the architecture of the cluster in the full article.

"ARM based servers hold the promise of extremely low power and excellent performance per Watt ratios. It's theoretically possible to place an incredible number of servers into a single rack; there are already implementations with as many as 1000 ARM servers in one rack (48 server nodes in a 2U chassis). What's more, all of those nodes consume less than 5KW combined (or around 5W per quad-core ARM node). But whenever a new technology is hyped, it's important to remain objective. The media loves to rave about new trends and people like reading about "some new thing"; however, at the end of the day the system administrator has to keep his IT services working and convince his boss to invest in new technologies."

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