AMD Radeon HD 7770 & 7750 Launch Review - PAGE 5

Next up to bat is the Cape Verde Pro GPU. Like its older sibling, the Pro version was designed to fit into the mainstream market but the performance is slightly lower, allowing it to retail for a lower MSRP. The Cape Verde Pro core has the same 1.5 billion transistors and is built on a 28nm node with a die size of just 123mm². However, what is different is the GPU has only 8 compute units, giving it a total of 512 streaming processors, 16 ROPS and 32 texture units. With these internal specs and an 800MHz GPU clock, the HD 7750 has a total compute power of 819 GFLOPs. Additionally, the HD 7750 has the same 128-bit 1GB GDDR5 frame buffer as the HD 7770, though the clock speed on this model is set at 1125MHz (4.5Gbps QDR) to give it a bandwidth rating of 72Gb/s, same as the HD 7770.

Visually the style and length of the HD 7750 look similar to graphics cards traditionally found in the entry-level segment. This isn't necessarily a bad thing though. Essentially what this means is that with the 28nm node, AMD has been able to reduce the power requirement to fewer than 75 watts so there is simply no reason to include a large PCB or heatsink. That said, this design is not going to be seen in the wild to great degree because like the HD 7770, most retail models with have a custom design. One really nice aspect of this design is the size. At just 6.75 x 0.75 x 4.25 the HD 7750 can fit into any mid-sized case, and some SFF cases as well.

Like the other cards in the Southern Islands family, the HD 7750 utilizes a Gen 3 PCIe interface which gives the card up to 32 GB/s of bi-directional bandwidth on an x16 connector. In comparison to the HD 7770, the HD 7750 has a simple design that lacks add-on voltage regulation circuitry, CrossFireX connectors, and a power connector. While the board doesn't include a CrossFIreX connection point, the technology is supported for up to two cards.

Since the PowerTune rating of the HD 7750 is only 55 watts, all the power is supplied to the board via the PCIe slot, and not a 6-pin power connector. Like the HD 7770, the HD 7750 comes with support for AMD ZeroCore power, which reduces the long idle power rating to below 3 watts. With a power rating of just 55 watts and a host of power saving features, the HD 7750 should be one hell of a power efficient graphics card.

The HD 7750 marks the first graphics card in the Southern Island family to not include four video outputs standard. What is included is a single 1.2 DisplayPort output, a HDMI 1.4a output and a DL-DVI output. Even while the configuration is slimmed down from the more expensive models, the HD 7750 can still support Eyefininty, HD3D technology and 3GHz speeds with frame packing via the HDMI connector. So, while this graphics card has a low MSRP it still has plenty of video expansion options.

The heatsink design used on the HD 7750 is extremely simple. It has a large shroud that covers rows of vertical pillars and a centrally mounted fan. Again, this is more like a solution that would traditionally be found on entry-level graphics cards, but with the thermal envelope being reduced below 75 watts it should get the job done. Additionally, the heatsink has a large metal base with a contact area for the GPU and four screw holes to attach it to the core.

The only aspect of the graphics card that looks anything like what we have seen thus far from the Southern Islands graphics cards is the red stripe running down the middle.

The Cape Verde Pro PCB has a similar layout to that of the HD 7770. Located at the front is the VRM followed by the memory and the 123mm² Cape Verde Pro GPU. Once again there are four memory modules on the PCB that are manufactured by HYNIX and have a 256MB capacity. This gives the board a grand total of 1024MB worth of graphics memory running on a 128-bit bus. This gives it roughly the same memory interface as the HD 6700-series (albeit with a high bandwidth rating) so we aren't expecting any massive performance increases over the previous generation when it comes to gaming at high resolutions.