AMD and Phenom II - everybody knows the name of current overclocking darling. Manufacturing wizards at GlobalFoundries tweaked up the 45nm SOI [Silicon-On-Insulator] with Silicon-Germanium material and enabled a flexible transistor design.
Combine that manufacturing skill with architectural improvements and the results are in: World Record for a multi-core CPU goes to Phenom II 955, originally clocked at 3.2 GHz. The team of overclockers in LimitTeam, consisted out of Sigh, Qooitry and Ultra40 overclocked the Phenom II 955 to 7,127.85 MHz, or 7.13 GHz, using a HyperTransport base clock of 250 MHz.
The team used ASUS M4A79T Deluxe motherboard, ATI Radeon 4800 series graphics card and 2x2GB of DDR3-833 memory by Apacer Technology. You can see the screenshot of CPU-Z validated score on the left, and the Phenom II firstname.lastname@example.org GHz project ID is 556849.
Both the graphics and memory were seriously underclocked to achieve as high clock as possible, with processor eating all the juice that motherboard was able to give.
This CPU belongs to Deneb's C2 revision, equal to the one we have in our Labs. So far, our Phenom II 955 achieved stable 4.1 GHz clock on air... it would be really, really interesting to see could this 7.1 GHz overclock pass the Linpack test... that score would be sure to give a lot of wet dreams to HPC administrators and engineers.
In any case, kudos to the LimitTeam and AMD for making a seriously overclockable processor.