To overclock today we are using the latest version of Sapphire's TriXX software tool.
We overclocked the card with a little increase in board power. We managed to get the core stable at 1039mhz, from 860mhz – translating to a 20.8% increase. The GDDR5 memory could be pushed from 1,250mhz (5,000mhz effective) to 1,408mhz (5,632mhz effective), translating to a 12.6% increase. Both really impressive results.
How does this affect the performance?
An increase of over 1,000 points in 3DMark 11 is not to be sniffed at. The Sapphire HD7950 Dual-X FleX Edition actually outperforms the reference clocked HD7970 at these settings, and almost catches the overclocked MSI R7970 lightning!