by Sergey Lepilov
12/12/2011 | 06:24 AM
We don't seem to be welcoming new graphics cards with high-end GPUs from AMD or Nvidia this year or even in the first quarter of 2012, so we have to limit our tests to what we have at hand. Today it’s Sapphire Radeon HD 6970 2GB GDDR5 DualFan. The company has actually released two graphics cards with the AMD Cayman processor, the other being Sapphire Radeon HD 6970 2GB GDDR5, but the DualFan version is the more exciting of the two due to its specs and cooling system. We'll see how good the new card is and benchmark it in comparison with same-class products in this review.
The graphics card comes in a large and pretty-looking box embellished with a picture of a sword-wielding fantasy girl. Key product features and supported technologies are listed nearby.
There is some more technical information along with a list of accessories on the back of the box.
This colorful wrapper covers a robust box with the graphics card. Below the latter you will find the following accessories:
Sapphire Radeon HD 6970 2GB GDDR5 DualFan costs $359, which is comparable with the majority of Radeon HD 6970 based graphics cards from other manufacturers.
The Sapphire Radeon HD 6970 2GB GDDR5 DualFan looks splendid with its stylish plastic casing and two fans with glossy black impellers.
The card is ordinary in terms of size: 270 x 111 x 45 millimeters.
It’s got a full selection of interfaces including one dual-link DVI-I port, one DVI-D, one HDMI 1.4a, and a couple of mini-DisplayPorts.
Included with the card is a mini-DisplayPort->DisplayPort 1.2 adapter. Besides the numerous connectors, there is a vent grid in the mounting bracket to exhaust the hot air out of the system case. This grid doesn’t do much for this card because of the design of its cooler that we'll discuss later on.
There are two MIO connectors for building CrossFireX configurations and a BIOS switch on the PCB:
One 8-pin and one 6-pin power connector are located in the top right corner of the card.
A 550-watt or better PSU is recommended for a computer with a single Radeon HD 6970. If you've got two such cards running in CrossFireX mode, your PSU should be 750 watts or better.
The card has a second-revision reference PCB and features a digital eight-phase power system based on a CHiL Semiconductor CHL82289 controller.
There are small black-painted aluminum heatsinks on the power circuit components, installed via thermal pads.
The card’s Cayman GPU was manufactured in Taiwan in late August (week 34).
The GPU has the standard Radeon HD 6970 configuration with 1536 unified shader processors, 96 texture-mapping units and 32 raster operators. The GPU frequency is 880 MHz at a voltage of 1.174 volts in 3D mode, which complies with the reference Radeon HD 6970 specs. A special feature of the Sapphire version is that it increases its GPU voltage to 1.2 volts at high loads in order to keep the GPU stable, which helps at overclocking. The second BIOS chip sets the standard voltage for every 3D mode, though. The GPU clock rate is lowered to 250 MHz at 0.9 volts in 2D applications.
There is nothing extraordinary about the graphics memory. The new Sapphire is equipped with 2 gigabytes of GDDR5 memory manufactured by Hynix Semiconductor in eight FCFBGA chips you can see on the face side of the PCB.
Labeled H5GQ2H24MFR R0C, these chips have a rated voltage of 1.6 volts and a clock rate of 6000 MHz, but the card clocks them at 5500 MHz, in strict compliance with the official Radeon HD 6970 specs. The memory clock rate is lowered to 600 MHz in 2D mode. The memory bus is 256 bits wide.
Here is a summary of the Sapphire Radeon HD 6970 2GB GDDR5 DualFan specs:
Now we can proceed to examining its most exciting cooler.
The cooler consists of five copper heat pipes, one aluminum heatsink, and a plastic casing with two fans.
Piercing the slim aluminum fins, the pipes distribute heat uniformly within them.
The pipes are soldered to the fins as well as to the copper base to ensure higher efficiency. The base has grooves for the pipes to lie in. The two outermost pipes are 8 millimeters in diameter whereas the three internal ones are 6 millimeters.
This design must be meant to ensure uniform transfer of heat from the GPU and increase the overall efficiency of this cooler.
The two fans are 90 millimeters in diameter.
Their speed is PWM-regulated within a range of 1100 to 3200 RPM. According to the stickers on the fans, they are manufactured by FirstD and have a max power draw of 4.2 watts.
We tested the efficiency of the cooler while running five cycles of the Aliens vs. Predator (2010) benchmark at the highest settings, at a resolution of 2560x1600 pixels, with 16x anisotropic filtering and 4x FSAA.
Our monitoring tools were MSI Afterburner 2.2.0 beta 9 and GPU-Z 0.5.6. Every test was carried out with a closed system case at an ambient temperature of 25°C.
Sapphire's DualFan cooler proved to be highly efficient both at its maximum speed and in the automatic regulation mode.
Max rotation speed
The GPU temperature was only as high as 67°C in the automatic mode, the fans rotating at 2500 RPM. At the full speed of 3200 RPM the temperature wasn’t higher than 64°C. The result is excellent, but what about noise? Let’s compare it with the noise level of Sapphire Radeon HD 6950 Toxic Edition and MSI N580GTX Lightning Xtreme Edition:
* The dotted lines refer to the maximum speed of the fan(s) when regulated automatically.
Indeed, the Sapphire DualFan is quieter than its two opponents. The cooler of the Sapphire Radeon HD 6950 Toxic Edition is similar to the reference one and has no chance in this comparison, but MSI's cooling system is quite competitive and comparable in noisiness to the DualFan in the automatic regulation mode. Still, we have to note that none of these original coolers is really quiet or even comfortable in 3D applications. If you want silence, you need something more efficient, like the Arctic Accelero XTREME Plus II, for example.
Our Sapphire Radeon HD 6970 2GB GDDR5 DualFan could be overclocked to GPU and memory frequencies of 990 MHz and 5880 MHz, respectively. That's a good result.
Radeon HD 6970s do not usually overclock more than 950 MHz in terms of GPU frequency, but Sapphire's version has an efficient cooler and increases the GPU voltage to 1.2 volts. Unfortunately, the card’s memory chips weren't very good at overclocking.
The card didn’t get much hotter when overclocked. The GPU temperature reached 72°C, the fans rotating at 2660 RPM in the automatic regulation mode.
We can remind you that Radeon HD 6970s with reference coolers are 15 to 20°C hotter than the Sapphire card with DualFan cooler.
We benchmarked our Sapphire Radeon HD 6970 2GB GDDR5 DualFan using AMD Catalyst 11.11c.
Our testbed included a six-core Intel Core i7 Extreme Edition i7-980X processor overclocked to 4.5 GHz.
We'll compare the results to those of the MSI N580GTX Lightning Xtreme Edition 3GB and Sapphire Radeon HD 6950 2GB Toxic Edition, the latter offering a unique opportunity of transforming it into an HD 6970 with a simple switch.
The Sapphire Radeon HD 6950 2GB Toxic Edition was tested in HD 6950 mode, though, so that we could see the difference in performance from the original HD 6970 in the form of the Sapphire Radeon HD 6970 2GB GDDR5 DualFan. Now let’s see what we’ve got in each individual test.
We don’t see anything unexpected here. The Sapphire Radeon HD 6970 2GB GDDR5 DualFan is somewhat faster than the Sapphire Radeon HD 6950 2GB Toxic Edition and predictably slower than the MSI N580GTX Lightning Xtreme Edition. When overclocked to 990/5880 MHz, it is close to the MSI card in Aliens vs. Predator (2010) and in the high-quality mode of Batman: Arkham City.
The Sapphire Radeon HD 6970 2GB GDDR5 DualFan is yet another top-quality premium-class graphics card based on an AMD GPU. It features a highly efficient cooling system which is much quieter than the reference Radeon HD 6970 cooler. It also has a second BIOS chip that sets an increased GPU voltage to help you reach higher frequencies at overclocking, especially as the DualFan cooler easily copes with the card even in overclocked mode.
The Sapphire Radeon HD 6970 2GB GDDR5 DualFan would be perfect if it came with some popular game in the box and at a lower price ($25-30 below the recommended price would be enough). This would make it a bestseller until the next generation of GPUs and graphics cards come about.