Well, this changes some things. AMD has just announced its intention to build 64-bit CPUs compatible with the ARM instruction set, starting with a multi-core SoC targeted at servers and eventually expanding into other markets. The first server-oriented chip will be branded as an Opteron and is expected to ship in 2014, complete with integrated support for AMD's Freedom Fabric interconnect for dense servers.
I'm going to post the bulk of the press release below, since it offers some additional details worth knowing—and since this is pretty huge news in the CPU space.
SUNNYVALE, Calif. — Oct. 29, 2012 — In a bold strategic move, AMD (NYSE: AMD) announced that it will design 64-bit ARM technology-based processors in addition to its x86 processors for multiple markets, starting with cloud and data center servers. AMD’s first ARM technology-based processor will be a highly-integrated, 64-bit multicore System-on-a-Chip (SoC) optimized for the dense, energy-efficient servers that now dominate the largest data centers and power the modern computing experience. The first ARM technology-based AMD Opteron processor is targeted for production in 2014 and will integrate the AMD SeaMicro Freedom supercompute fabric, the industry’s premier high-performance fabric.
AMD’s new design initiative addresses the growing demand to deliver better performance-per-watt for dense cloud computing solutions. Just as AMD introduced the industry’s first mainstream 64-bit x86 server solution with the AMD Opteron processor in 2003, AMD will be the only processor provider bridging the x86 and 64-bit ARM ecosystems to enable new levels of flexibility and drive optimal performance and power-efficiency for a range of enterprise workloads.
"AMD led the data center transition to mainstream 64-bit computing with AMD64, and with our ambidextrous strategy we will again lead the next major industry inflection point by driving the widespread adoption of energy-efficient 64-bit server processors based on both the x86 and ARM architectures," said Rory Read, president and chief executive officer, AMD. "Through our collaboration with ARM, we are building on AMD’s rich IP portfolio, including our deep 64-bit processor knowledge and industry-leading AMD SeaMicro Freedom supercompute fabric, to offer the most flexible and complete processing solutions for the modern data center."
"The industry needs to continuously innovate across markets to meet customers’ ever-increasing demands, and ARM and our partners are enabling increasingly energy-efficient computing solutions to address these needs," said Warren East, chief executive officer, ARM. "By collaborating with ARM, AMD is able to leverage its extraordinary portfolio of IP, including its AMD Freedom supercompute fabric, with ARM 64-bit processor cores to build solutions that deliver on this demand and transform the industry."
The explosion of the data center has brought with it an opportunity to optimize compute with vastly different solutions. AMD is providing a compute ecosystem filled with choice, offering solutions based on AMD Opteron x86 CPUs, new server-class Accelerated Processing Units (APUs) that leverage Heterogeneous Systems Architecture (HSA), and new 64-bit ARM-based solutions.
This strategic partnership with ARM represents the next phase of AMD’s strategy to drive ambidextrous solutions in emerging mega data center solutions. In March, AMD announced the acquisition of SeaMicro, the leader in high-density, energy-efficient servers. With today’s announcement, AMD will integrate the AMD SeaMicro Freedom fabric across its leadership AMD Opteron-, ARM- and x86-based processors that will enable hundreds, or even thousands of processor clusters to be linked together to provide the most energy-efficient solutions.
We're seeking clarifications on some points of interest and will post an update once we have them.
Update: Some folks have taken this announcement to mean that AMD will be giving up on x86-compatible CPUs going forward. That's very much not the case. Even the press release says the ARM chips will come "in addition to its x86 processors for multiple markets."