The AMD product lineup had a small hole in it for a long time between the HD 7770 and the HD 7850. We heard a few rumors about the possibility of an HD 7790 or an HD 7830 and just after LanOC V12 AMD launched their answer the HD 7790. We are a little late to the party, but we have had time to put ours to the test with our revamped benchmark suit that features the latest games. Let’s take a look at how it performs compared to AMD’s other offerings as well as NVidia’s new GTX 650 Ti Boost. Is this a good time to pick up a new video card?
Product Name: XFX R7790 Black Edition OC
Review Sample Provided by: XFX
Written by: Wes
Pictures by: Wes
What’s the HD 7790 all about
Before we jump into our review lets go over the details of the HD 7790. Nvidia put together their GTX 650 Ti Boost using a GTX 660 PCB and memory with a GTX 650 Ti Graphics Chip. AMD didn’t take that route though with the HD 7790. They actually put together a different Graphics Chip specifically for the HD 7790. This is obvious when taking a look at the specifications for the HD 7770, HD 7790, and HD 7850. The HD 7790 has 2.08 billion transistors while the HD 7770 has 1.5 and the HD 7850 has 2.8. Along with that the HD 7790 has 656 texture units over the 40 from the HD 7770 and the HD 7850’s 64. Where the HD 7790 does match the HD 7770 is with its Memory Interface. It has the same 128 bit interface with 1 gig of GDDR5. The HD 7850 does have the same 128 bit interface but with twice the ram it will have less issues with high resolutions and extremely demanding games.
The HD 7790 is still based on AMD’s Graphics Core Next architecture as well as 28nm technology. You will get dual geometry and tessellation engines as well. Here is a breakdown of its architecture.
They did make another change with the HD 7790, a tweak to their AMD PowerTune Technology that dynamically overclocks your card on the fly. Previously PowerTune used four DPM states, low power, intermediate, high, and boost. Each would run different clock speeds and dynamically adjust voltage as needed. The HD 7790 had eight DPM states allowing for a better voltage selection as clock speeds ramp up. This doesn’t change the boost speed really but can play a big role in you getting the best performance in everyday use. What that means is with smaller steps it is more likely that there will be a power state that will fit the clock speed that you might be using, making it more efficient.