With the paper launch of the Radeon HD 7970 last week, we are starting to get more leaked information about the other models hitting the market under the new "Tahiti" platform. In the information leaked by xtreview, The HD 7950 will have 1792 stream processors, 28 GCN compute units, which is down 256 stream processors from the HD 7970. It will utilize a 384-bit memory bus and 3GB GDDR5 just like the HD 7970. The HD 7950 looks to utilize 112 texture units and 32 full color ROPs. It has support for a maximum of 6 displays. What is still unknown at this time is the core clock speed, memory clock speed and price point. With the HD 7970 set to release around $550, I would expect the HD 7950 to fall closer to the $400 price mark at release.
AMD is expected to release its flagship dual-GPU graphics card based on the "Tahiti" platform in 2012. We are learning under the codename "New Zealand", AMD is working on the monster HD 7990, which will utilize two HD 7970's and 6GB of total graphics memory (3 GB per GPU system). If AMD will indeed go for the HD 7970, this could mean that the card will include 62 compute units for a total of 4096 stream processors, 256 texture units and 64 full color ROPs.
One thing that will benefit the HD 7990 is AMD's new ZeroCore technology. ZeroCore technology completely powers down other GPUs, other than the primary one, to zero state, when the system is not running graphics-heavy applications (though as discussed in our review of the HD 7970, this feature still needs to be verified). This means at idle, desktop or video playback state, the HD 7990's power draw will be nearly equal to that of the HD 7970, which through early testing was impressive.
Early reports have the HD 7990 set to release around March, 2012 with a hefty price tag.