" Like AMD’s other recent high-end CPU launches, today’s Athlon 64 X2 6000+ processors are based on AMD’s 90-nm Windsor core, if you recall AMD’s Quad FX processors are also built at 90-nm. From a business perspective, it makes sense for AMD to focus most of their 65-nm production on less expensive CPUs first as these processors tend to carry lower profit margins anyway. Once their 65-nm process is more mature, AMD can then introduce faster 65-nm parts at higher clock speeds."
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