OCC has published a review on the Corsair Vengeance 8gb (2X4 GB) PC3-12800 Cas9 memory

The Corsair Vengeance memory managed an increase of it's frequency to 1980 Mhz with only a slight bump in the tRCD timing from 9 to 10 and an increase of the tRAS from 24 to 27 and also an increase of the vDimm to 1.65v. The memory ran completely stable at this elevated frequency and proved to boost the performance of this set of RAM in our testing.

  Corsair Vengeance 8gb (2X4 GB) PC3-12800 Cas9 Review