Datacenters 301
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Power
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PUE (Power Usage Effectiveness)
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3 phase power
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Note you can't use a wire clamp to measure a 3-phase power cable, you need to 
measure each phase by itself.

DC power
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48V (telco land, NEBS standard) and other versions that are being tried, 
(12, 24V).
Grounding requirements, power bars. Devices often have different plugs.
Most of the time still using A+B circuits
Reduced conversions == Reduced losses. Amplified by most larger servers (i.e. 
HP C7000, SuperDome) using 48V internally.
Even more interesting with large UPS banks since those also use 48V.

Increasing cooling efficiency
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CFM
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Hot aisle / cold aisle design fundamentals
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Hot aisle / cold aisle containment
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Chimneys 
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Design Options
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Raised floor (18in & 36in)
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