For comparison was the Radeon HD 6950 "Cayman" at its reference clock speeds of 800/1250MHz. At the moment I still do not have a NVIDIA GeForce GTX 680 "Kepler" for comparison, but am told one should ultimately be coming. (Besides the HD 6950, those looking for more comparative results can find the greater NVIDIA/AMD card selection in the prior HD 7950 article.)
In terms of the open-source Radeon HD 7000 series support on Linux, since the earlier HD 7950 article, AMD did publish the KMS/DRM driver support code for integration into the mainline Linux 3.4 kernel. However, as of 29 March, there still is not the new Gallium3D driver available to provide for 3D/OpenGL acceleration with these new AMD GPUs.
Aside from using the different driver that officially supports the Radeon HD 7950 and running the card at the different clock speeds, the testing is similar to the results from earlier this month. Those wanting to see how their system's own OpenGL performance compares to the results in this article, it is simply a matter of having the Phoronix Test Suite installed and then running phoronix-test-suite benchmark 1203223-BY-RADEONHD720. At the end of this article are also some thermal results for the Radeon HD 7950 under Ubuntu Linux.