AMD Radeon HD 6870 Memory Voltage Pencil Mod
 

We managed to gain an extra 40MHz on the graphics memory with the aforementioned memory voltage, and a corresponding improvement in graphics performance.

This puts us at 1180MHz on the memory frequency, 20MHz short of the 1.2GHz ballpark, but that shall be something you readers can try out - for next to zero cost!

http://vr-zone.com/articles/amd-rade...cil/10160.html