Hillsboro (OR) - AMD is preparing the rollout of its first quad-core processor, an Opteron processor based on the Barcelona core. Meanwhile, Intel is developing an answer to Barcelona: The company is lining up 45 nm server and desktop processors and will revive Hyperthreading in 2008 with the Nehalem core.

Sources indicated that Intel acknowledges AMD's claim that the company has developed a "true" quad-core processor, while Intel is relying on a dual-die package with two dual-core processors at this time as well as 45 nm Penryn quad-core CPUs. However, the company also believes that AMD's decision to integrate the memory controller into the CPU has a downside and forces the manufacturer to compromise cache size and stick to only two memory channels.

Intels' initial answer to AMD's Barcelona quad-core will be the "Harpertown" processor for servers and "Yorkfield" for desktop PCs. Both chips will be based on a 45 nm shrink of the current Core architecture and continue to use a multi-chip-package for quad-core CPUs. Intel claims that the multi-chip package provides a flexibility that "enables Intel chip designers to put two cores in one package, which AMD can't do in such a straightforward way," sources indicated.

Things will get a bit more interesting with the introduction of the Nehalem core - an evolutionary step up from the Core microarchiteture. Sources said that the Nehalem architecture will result in performance gains in the range between 20 and 40%. The architectural changes in Nehalem will bring new instructions as well as a new shared cache, which, according to sources, will grow to 12 MB. Intel will also revive its Hyperthreading technology, which will be called "symmetric multi-threading" (SMT).It basically represents a multi-core adaption of the original Hyperthreading idea that was first introduced with single-core Pentium 4 processors in 2002.

Hyperthreading originally simulated a second virtual core within a physical core CPU and was the first step to take advantage of multi-threaded applications on the desktop. In the 45 nm market, this technology would simulate four additional threads in quad-core processors and eight additional threads in eight-core processors (for a total of 16), which are expected to debut in the 45 nm generation of Intel processors.

Source : Tom's Hardware US