In our review of the HD 7970, we were able to push the GPU clock speed up to 1125Mhz with no additional voltage. However, since the graphics card we reviewed was BIOS limited there was no chance to push it further, so we couldn't tell how much additional headroom was left. According to sources over at Chiphell, the HD 7970 is capable of scaling above 1300MHz.
Sapphire is going to release two SKUs clocked at 1335MHz, and both are going to be part of the Atomic series. The difference between the two models is the RX utilizes an air cooled thermal solution, while the WX is going to be water cooled. Sapphire also has a full lineup for the HD 7970 including reference models and even one with a 6GB GDDR5 memory buffer.
The most interesting aspect of the image though is not what is clearly visible, but what has been crossed out. At the top of the image are two graphics cards listed with a steaming processor count of 2304. Now we all know the HD 7970 has 2048 streaming processors, and we haven't heard anything regarding a Southern Islands GPU with a higher SP count. This caught our eye, so we did a little digging and found it to be just one version of the Tahiti XT GPU AMD was testing prior to launch, and also that (according to sources at PC Perspective) it doesn't include any unlockable SPs. Still, it is interesting to see manufacturers were actively preparing for a HD 7970 with 2304 streaming processors.
This could also potentially mean AMD have in their possession a stronger GPU than the current flagship Tahiti XT core, which they could release to counter Kepler later this year. If such a GPU exists, it could potentially be up to 25% to 45% faster than the HD 7970, depending on the clock speed -- possibly a HD 7980 or 8970.