Two just-in reports suggest AMD has a success on its hands with its new 6-core Istanbul. Early tests are showing that the processor, which is a drop-in replacement on mobos supporting quad-core 'Shanghai' Opterons, delivers great performance while being very power-efficient.One top-line comparison appears on TechReport, which found in its test that "Istanbul's showing represents a solid advance over Shanghai [which is the current quad-core Opteron]."

While TechReport found that a Xeon 5550 system inched out the Istanbul Operton 2435 on a specific SPECpower benchmark, it rendered this positive verdict: "Make no mistake, though: this Istanbul system is very much a match for the Xeon in terms of power-efficient performance."

Speaking to the back-compatibility of Istanbul, TechReport added: "If you have existing, compatible Socket F servers, the Istanbul Opterons should be an excellent drop-in upgrade. They're a no-brainer, really, when one considers energy costs and per-socket/per-server software licensing fees."

Credit to Ars Technica's Jon Stokes who put together a nice summary on Tuesday, pointing to the TechReport item as well as another lengthy Istanbul review on AnandTech.

The AnandTech piece, by Johan De Gelas, comes to the conclusion that the Xeons are generally more versatile but that: "There are two types of applications where we feel that the AMD six-core deserves your attention: decision support databases and virtualization."

Also -- and this is a big deal as far as the high-end, four-socket-server market -- De Gelas says this: "The six-core Opteron will be a formidable competitor in the 4P market segment."

There are a lot of interesting, high-end implementations around, in 4- and 8-socket configurations, and more. For example, Microway has a product it calls Navion, which packs two Istanbuls in each 1U node. You can cram a whole bunch of those thin nodes into a larger rack, to create a cluster with a density of 960 cores and 240 TBytes of storage.

This movement to ever higher densities -- both on the processor and server level -- won't end anything soon. Visual proof is posted over at SemiAccurate.com, where Charlie Demerjian has acquired pictures of upcoming motherboards containing Magny Cours, which is the 12-core part due from AMD in 2010.

Here once again are some recent AMD Istanbul (and Intel Nehalem) slides:

AMD's six-core 'Istanbul' Opteron server processor.(Click picture to enlarge and to see three more shots.)

Intel's Nehalem-EX eight-core server processor.(Click picture to enlarge and to see three more shots.)

See also: AMD Poised To Launch 6-Core Istanbul

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