Opteron is AMD's x86 former server and workstation processor line, and was the first processor which supported the AMD64 instruction set architecture (known generically as x86-64). It was released on April 22, 2003, with the SledgeHammer core (K8) and was intended to compete in the server and workstation markets, particularly in the same segment as the Intel Xeon processor. Processors based on the AMD K10 microarchitecture (codenamed Barcelona) were announced on September 10, 2007, featuring a new quad-core configuration. The most-recently released Opteron CPUs are the Piledriver-based Opteron 4300 and 6300 series processors, codenamed "Seoul" and "Abu Dhabi" respectively.
In January 2016, the first ARMv8-A based Opteron-branded SoC was released, though it is unclear what, if any, heritage this Opteron-branded product line shares with the original Opteron technology other than intended use in the server space.
Opteron combines two important capabilities in a single processor:
native execution of legacy x86 32-bit applications without speed penalties
native execution of x86-64 64-bit applications
The first capability is notable because at the time of Opteron's introduction, the only other 64-bit architecture marketed with 32-bit x86 compatibility (Intel's Itanium) ran x86 legacy-applications only with significant speed degradation. The second capability, by itself, is less noteworthy, as major RISC architectures (such as SPARC, Alpha, PA-RISC, PowerPC, MIPS) have been 64-bit for many years. In combining these two capabilities, however, the Opteron earned recognition for its ability to run the vast installed base of x86 applications economically, while simultaneously offering an upgrade path to 64-bit computing.
The Opteron processor possesses an integrated memory controller supporting DDR SDRAM, DDR2 SDRAM or DDR3 SDRAM (depending on processor generation). This both reduces the latency penalty for accessing the main RAM and eliminates the need for a separate northbridge chip.