The AMD Radeon HD 6790 (Cont’d)

In Figure 4, you can see the video card with its cooler removed and, in Figure 5, a close-up of the voltage regulator circuit.

AMD Radeon HD 6790 reference modelFigure 4: Video card with the cooler removed

The voltage regulator circuit of the reference model uses solid capacitors, ferrite-core coils (which make the regulator to have higher efficiency because they have lower energy loss than iron-core coils), and low RDS(on) MOSFET transistors (i.e., higher efficiency). This circuit uses a four-phase design to generate the GPU voltage.

AMD Radeon HD 6790 reference modelFigure 5: Voltage regulator circuit

The GPU heatsink can be seen in Figures 6 and 7. It has a copper base, three copper heatpipes (two five-mm and one eight-mm), aluminum fins, and a 75 mm radial fan.

AMD Radeon HD 6790 reference modelFigure 6: The GPU heatsink

AMD Radeon HD 6790 reference modelFigure 7: The GPU heatsink

The Radeon HD 6790 reference model uses eight 1 Gbit GDDR5 memory chips, making its 1 GB memory (1 Gbit x 8 = 1 GB). The chips used are H5GQ1H24AFR-T2C parts from Hynix, which support up to 1.25 GHz (5 GHz QDR). Since on this video card memory is accessed at 1 GHz (4 GHz QDR), there is still a huge 25% margin for you to increase the memory clock rate while keeping the chips inside the maximum they support. Of course you can always try to overclock the memory chips above their specs.

AMD Radeon HD 6790 reference modelFigure 8: Memory chips

Before seeing the performance results, let’s recap the main features of this video card.

Gabriel Torres is a Brazilian best-selling ICT expert, with 24 books published. He started his online career in 1996, when he launched Clube do Hardware, which is one of the oldest and largest websites about technology in Brazil. He created Hardware Secrets in 1999 to expand his knowledge outside his home country.