As we have seen from AMD’s previous slides, during the launch of the 7900 series, the “Southern Islands” line is divided in three segments each having different performances. First we have the “Tahiti”, which is the new high end and incorporates the Radeon HD 7970 and 7950 cards, “Pitcairn”, which cards are not launched yet and of course, “Cape Verde”, which aims at the budget conscious people, and is meant to bring a good balance between power, price and power consumption.
The representatives of “Cape Verde” are Radeon HD 7750 and 7770 and the card we will look upon now is the XFX Radeon HD 7770 Black Super Overclocked Edition, featuring Double Dissipation. As the name says, this model is pre-overclocked and features a dual fan cooling system. Here are the differences in specifications between the OEM model from AMD and the offering from XFX:
Like the 7970, the 7770 cards are built upon the 28nm architecture and come with the same features as the high-end GPUs; from these we can enumerate Eyefinity 2.0, PowerTune, ZeroCore Power, DX 11.1 hardware support, PCI-E Gen 3 and so on.
At this point you may say: cool, but what has been cut then to meet these price points? Well, AMD has reduced the GPU architecture to 10 compute units (640 stream processors) and now the memory bus is only 128-bit wide. The smaller brother, Radeon HD 7750 has 512 stream processors and shares the same 128-bit memory bus.
Like at any new GPU launch, manufacturers also bring on the market pre-overclocked editions. For the 7770 series, XFX comes with the Radeon HD 7770 Core edition and Radeon HD 7770 Double Disipation Edition, which sport the clocks of the OEM model; next, there is the Radeon HD 7770 Black Edition along with the Double Disipation Edition which have the GPU clock raised to 1095MHz. Lastly we have the highest clocked card from the bunch, the Radeon HD 7770 Black Super Overclocked Edition featuring Double Dissipation.