Shanghai, the 45nm core from AMD, is likely to debut late this year. It will be similar in many aspects to the currently-availabe B3 stepping of the Socket 1207 Opteron (Barcelona) shipping today. Unlike Barcelona however, which has its HyperTransport 3.0 clock generator fused off, Shangai should utilize HyperTransport 3.0 for inter-CPU communication. Also, AMD has a new "native six-core" Shanghai derivative in store, currently codenamed Istanbul. This processor is clearly targeted at Intel's recently announced six-core, 45nm Dunnington processor. AMD plans to utilize 2 Istanbul cores to create a 12-core CPU, where both cores will communicate with each other via HyperTransport 3.0. A quad-channel memory controller may also be possible. All new Shanghai CPUs should be backwards compatible with existing Socket 1207 motherboards.

Shanghai is currently taped out and running Windows at AMD.Source: DailyTech