The Graphics Core Next architecture is something that many gamers are yet to fathom. But with the AMD Radeon HD 7970 on the horizon, the awesome graphics processing capabilities of a 32 Compute Unit GPU.
That’s 2048 streaming cores that operate at a 925MHz clock. All this has been learned after leaked specifications have gotten out of the sack. What you will be seeing is speeds of 1.37GHz with 264GB/s memory
bandwidth, up for grabs.

The AMD Radeon HD 7970 is expected to roll out officially by January 9th, 2012. Till then we will not know what expect from the graphics card. 3GB VRAM maybe?

[Softpedia]