The HD 8790 is a mainstream GPU, based on the GCN architecture and, of course, it’s a 28nm part. However, it’s not quite the HD 8000 series part you will get in your desktop. Tom’s describes the HD 8790 as AMD’s effort to get GCN into the mobile space, as an experiment of sorts.
The GPU features 384 stream processors and a GPU clock of up to 850MHz, which is somewhat faster than what we’ve come to expect from the HD 7000 series. As expected, the new card delivers rock solid performance, but the early preview might not be the best indication of its potential performance.
However, not everything revolves around performance in the mobile space. According to the preview, the HD 8790 should be able to run in the same systems where you would typically find a Radeon HD 7670M. This means we should see more GPU muscle in relatively thin and light notebooks. In today’s ultrabook-centric market, that means a lot.
You can check out the preview here.