AMD Radeon HD 7790: Affordable DX11 Gaming

A few weeks back, the enthusiast community was abuzz after news broke that AMD’s Radeon HD 7000 series would remain “stable throughout 2013” and would be the company’s focus “for quite some time”. The wording of the initial news made it sound like AMD wouldn’t be releasing any new GPUs for the rest of the year and that it would further differentiate its offerings with only new game and software bundles.

AMD convened a conference call to try and quell the rumors and better explain the company’s position at the time, but short of saying there were some new products in the pipeline, not much was said to clarify the situation. Well, here we are, about a month out from the initial breaking of that news, and AMD is ready with a new mainstream graphics card, which features a brand new GPU.

Today AMD is taking the wraps off of the new Radeon HD 7790, a mainstream GPU designed to fill the gap in the company’s current graphics card lineup between the Radeon HD 7770 and HD 7850. The features, specifications, and details of the new Radeon HD 7790 GPU are below, with an array of benchmarks to follow...

The AMD Radeon HD 7790 Reference Card

AMD Radeon HD 7790 Specifications & Features

Above, we have the main features and specifications of the newly updated Radeon HD 7700 series. As you can see, the Radeon HD 7790 features a larger GPU with more stream processors and texture units than the 7750 and 7770 and double the geometry performance per clock, too. Pixel fillrates are similar, and all of the cards feature a 128-bit memory bus, but the Radeon HD 7790’s frame buffer will be clocked significantly higher (6Gbps vs. 4.5Gbps), which results in much more memory bandwidth.

The GPU featured on the Radeon HD 7790 is codenamed “Bonaire XT”. It is comprised of 2.08 billion transistors, has a die size of 160mm2, and is manufactured on TSMC’s 28nm process node. The Bonaire XT GPU is based on the same Graphics Core Next architecture of previously-introduced Radeon HD 7000 series cards and offers full support for DX 11.1.

There are a total of 896 stream processors in the GPU, arranged in 14 compute units with 64 SPs each. Like the Radeon HD 7900 / 7800 series, there are dual geometry and tessellation engines in the Radeon HD 7790 GPU, which doubles the primitive rate of the Radeon HD 7770 and 7750. There are 56 texture units, 16 ROPs in the Bonaire XT, and memory is connected via a 128-bit interface.

Radeon HD 7790 reference clocks call for a 1GHz GPU with 1.5GHz (6.0Gbps effective) memory. At those clocks, the Radeon HD 7790 offers up to 1.79 TFLOPS of compute performance, with texture and pixel fillrates of 56GT/s and 16GP/s, respectively, as well as 96GB/s of memory bandwidth.

In addition to beefing up the geometry and tessellation engines and upping the number of stream processors and texture units in the 7790 versus previous Radeon HD 7700 series cards, AMD also made some enhancements to its PowerTune technology with the Radeon HD 7790.

Whereas previous Radeon HD 7000 series cards with support for Boost offered four dynamic power management states, the Radeon HD 7790 has eight. The additional DPM states help ensure that the GPU is using optimal voltage at a given clock state and ultimately enables higher engine clock speeds. Switching DPM states happens in as quickly as 10ms and is based on GPU activity and current and thermal management limits.