AMD recently introduced the HD 7790, its first Bonaire-based card which fits snugly in between the HD 7770 and HD 7850, not to mention a couple of Nvidia cards. The new Bonaire GPU is a 28nm CGN part, optimized for superior power efficiency.

The specs have low-mid-range written all over them. Compared to Bonaire (HD 7790), the old Pitcairn Pro (HD 7850) has more stream processors (1024 compared to 896), more texture units (64 compared to 56), a faster memory interface (256-bit compared to 128-bit) and more ROPs (30 ROPs compared to 16 ROPs). As we can see, Bonaire's memory interface is a lot weaker than the HD 7850, but this shortcoming is partially offset by the use of speedy 6Gbps GDDR5 memory.

The Radeon HD 7770 also has a 128-bit memory interface, but it uses slower 4.5Gbps GDDR5, memory. Hence, its memory bandwidth is 72GB/s, compared to 96GB/s on the HD 7790. The rest of the specs, such as 640 stream processors and 40 texture units, are also behind the HD 7790.

Today we’ll take a very special HD 7790 card out for a spin. The XFX Black DD Radeon 7790 1075M Boost Edition is an overclocked card with a custom cooler. Its GPU is clocked at 1075MHz, while the memory ticks at 6400MHz. The reference clocks are 1000MHz for the GPU and 6000MHz for the memory.

The higher clocks are just one of the selling points. A strict selection process called ‘GPU Edging’ is used to identify the top 1 percent of GPUs capable of reaching maximum overclock speeds and with help of quality Duratec components (another marketing name for high end power components) XFX claims the highest performance and the lower power consumption in class.

Plenty of other AMD partners introduced overclocked HD 7790 cards, but none of them went over 1075MHz. It is clear that AMD suggested the highest clock for OC cards and we believe this was a marketing decision rather than a technical one. We were convinced that the HD 7790 could hit much higher clocks with relative ease and our overclocking tests proved us right.

In order to compensate for higher temperatures caused by the factory overclock, the Black DD R7790 card comes with a powerful Double Dissipation cooler – a cooler with a special heatsink and two fans which should cope with the demands of the Bonaire GPU with ease.

Thanks to AMD’s more than generous bundle scheme, the Radeon HD 7790 is eligible for a nice freebie in the form of Bioschock Infinite and Far Cry 3 Blood Dragon. However, prior to making your purchase please make sure that your retailer is participating in the promotion, just to stay on the safe side.