Jason Clark and Ross Whitehead at Anandtech.com take a look at the power efficiency and scalability of three similarly-priced low-voltage server processors from AMD and Intel.
If there was ever any doubt that Intel made a bad decision not going true quad-core, it should be clear with numbers like these that their decision was sound and is paying off. Quad-core processors may not be faster in every situation, but in heavily threaded CPU intensive environments the extra CPU cores are easily able to make up for any penalties associated with the dual-die packaging.
AMD’s newly-released Barcelona “native” quad-core offering was not available for testing at the time. However, based on the article’s detailed breakdown of each server component’s power drain (did you know Intel’s FB-DIMMS consume 862% more power than the AMD DIMMs?!), it looks as if Barcelona will be a very promising contender for the performance-per-watt-per-Kelvin crown.
Intel may be a year ahead in sheer manufacturing technology, but FB-DIMMs seem to be their Achilles heel in this end of the market. There are reports that Intel will add unbuffered DDR DIMMS to it’s DP server lineup in 2008, but I’d deem it wise to re-evaluate the entire roadmap.