XFX & Sapphire HD 7950 3GB Reviewccokeman -
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When I looked at the Sapphire Radeon HD 7970 3GB offering I was disappointed to see that it was a reference-based card. As AMDs largest partner, they usually pull something out of their hat in terms of custom cooling or in-house built boards and improved component selection. While the reference card was a let down in that sense, the first offering out of the gate on the second card in the 7 series product stack is a custom build. A first look shows a large dual fan cooling solution on top of a Sapphire built PCB. The 5 heat pipe cooler looks similar to that of the Double Dissipation cooling solution used on the XFX HD 7950. The back side of the PCB is for the most part featureless. The Sapphire HD 7950 OC measures slightly longer than the reference card due to the fan shroud that overhangs the end of the PCB. From the side, the large copper heat pipes are visible as they run from the copper base plate to the fin array. Clock speeds for this card are 900Mhz on the 28nm core and 1250MHz on the GDDR5 memory.
Display connectivity has been reduced to improve the acoustics and improve airflow through the mounting bracket. The 7 series remove one of the DVI ports to make way for these improvements. Even so there are plenty of options to connect up to six displays through this card via the pair of Diplayport 1.2 ports that can be used with a MST hub or daisy chaining a trio of Diaplay port monitors together off of each port. By using the card in this way, a six screen Eyefinity setup can be utilized. Eyefinity 2.0 brings new functionality and individual streaming of HD audio along with each separate video stream. A full-size HDMI port that supports the 1.4a standard is used as well. The rear of this card is open, allowing for unobstructed airflow out from under the heat sink fan shroud.
CrossfireX continues to be supported in configurations of up to four HD 7950s as long as the motherboard used supports it. Dual-bridge connections are used to connect to each card in the configuration. The power connections used are a pair of 6-pin PCIe connectors to deliver an additional 150 watts to the card. 500 watts is the recommended power supply size. The power connections on the PCB show that an 8-pin power connection is a thought for this video card series. A dual BIOS switch is included on the HD 7950 from Sapphire to allow for flashing a custom BIOS, recovering from a bad flash, or if one is lucky enough AMD hopefully left open the same doors they did on the HD 6950 allowing a flash to a HD 7970.
Pulling the card apart shows that Sapphire has taken a slightly different approach to cooling the HD 7950. The large shroud covers up a large five heat pipe-based cooling solution that does not incorporate a built or integrated heat sink/aluminum plate to cool the memory and stiffen the board. On this card from Sapphire they are separate parts. The heat sink has five large heat pipes that are soldered to the fin array to promote a better thermal transfer rate. The 10mm thick dual fans are made by FirstD.
The Sapphire HD 7950 is built using AMD's 28nm Southern Islands Tahiti core that features 112 texture units, 32 ROPs, 1792 shader cores, 3GB of GDDR5 memory running through a 384-bit bus. The GDDR5 memory used on the Sapphire HD 7950 is from Hynix as it seems all of AMD's high-end cards have been equipped over the past few launches. Part number H5GQ2H24MFR-T2C is used and is rated for operation at a clock speed of 1250MHz. Sapphire has bumped the core clock on this card up to 900MHz and runs with a memory clock speed of 1250MHz.
Sapphire has a good looking card that includes a bump in clock speed over the reference baseline clock speed on the core and ups the ante with a custom PCB and dual-fan cooling solution. Having seen what Sapphire has to offer, let's look at the XFX HD 7950 Black Edition before testing them both out.