AMD released six-core Opteron HE processors today that promise to up the performance per watt ante.

Currently shipping in 2-,4- and 8-processor HP ProLiant servers, the new Istanbul chips boast an nice percent performance per watt boost over their quad-core cousins.

AMD’s Andy Parma explains:

When we compare servers using the newest Six-Core AMD Opteron 2400 Series HE processors to servers using existing AMD Opteron processors, we find that a server based on the AMD Opteron 2400 Series HE processor is able to achieve 18% higher performance-per-watt than a server using Quad-Core AMD Opteron 2300 Series HE processors and also consumes 18% lower platform-level power than a server using Six-Core AMD Opteron 2400 Series processors.

For two-socket servers, there’s the 2.0 GHz Opteron 2423 HE ($455, all prices in thousand unit quantities) and the 2.1 GHz 2425 HE ($525), both operating at 55 watts. Four- and eight-socket systems get the 2.1 GHz Opteron 8425 ($1,514), which also operates at 55 watts.

AMD also released 2.8 GHz SE variants (2439 SE, $1,019 and 8439 SE, $2,649), but at nearly twice the power consumption (105W), they’re clearly meant for high-performance servers.

Dell is also planning to incorporate the processors, both HE and SE, in Dell PowerEdge blade and rack-mounted servers in the coming weeks.