AMD vs. Intel: power efficiency in the server room rests on RAM

Late last year, AMD responded to Intel's "Clovertown" Xeon launch by touting the differences between the power efficiencies of platforms based on its Opteron versus those based on Intel's dual-core "Woodcrest" Xeons. AMD did not (and still doesn't) have a quad-core answer to Clovertown, so the company played to its strengths by (rightly) emphasizing the performance per watt of Opteron-based systems viewed as a whole. Tech Report was one site that looked into AMD's claims and found that in spite of Intel's clear lead over AMD in CPU performance per watt, AMD's server platform has a substantial lead over Intel's when it comes to system-level power efficiency under certain significant types of load conditions. What this means is that when power is measured at the wall socket instead of at the processor socket, Opteron systems can give better performance per watt than Woodcrest systems.
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