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Former Intel CPU engineer details how internal x86-64 efforts were suppressed prior to AMD64's success
(www.tomshardware.com)
This is a most excellent place for technology news and articles.
Hence ARM. ARM already has designs for low power, high performance chips for smaller devices like laptops. Intel is chasing that market, and AMD could easily get a foot in the door by slapping their label on some designs, perhaps with a few tweaks (might be cool to integrate their graphics cores?). They already have ARM cores for datacenter workloads, so it probably wouldn't be too crazy to try it out on business laptops.