GIGABYTE Radeon HD 7970 OC Video Card Review

GIGABYTE has a custom cooled and overclocked version of the Radeon HD 7970. We examine how well GIGABYTE's Windforce 3X cooling technology allows us to overclock this next generation video card. Find out how this GIGABYTE GV-R797OC-3GD monster compares to a GeForce GTX 580, a Radeon HD 6970, and reference HD 7970.


GIGABYTE is a hardware manufacturer and one of the most respected PC component builders in the business today. The company was established in 1986 in Taipei, Taiwan, and is best known for its motherboards. GIGABYTE has a vast product line, including motherboards, graphics cards, notebooks, LCDs, mobile devices, tablet computers, computer cases, and many other PC peripherals.

Today we will be looking at GIGABYTE's first custom video card from the new HD 7000 series GPU, the GIGABYTE GV-R7970OC-3GD.

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AMD Radeon HD 7970

AMD announced its new Radeon HD 7970, code-named "Tahiti", on December 22nd, 2011. Product availability was made on January 9th, 2012. Tahiti represents a departure from previous architectures for AMD. It calls the new architecture "Graphics Core Next," or GCN. The Radeon HD 6000 series used AMD's VLIW 4 and 5 architectures. GCN features a smaller die at 28nm, compared to the 40nm process used for the previous generation.

Aside from the die shrink, GCN offers a number of features over previous generation GPUs. One particularly noteworthy feature is "ZeroCore Power." This feature disables unused GPUs (or portions of those) during long idle periods to save power and increase efficiency. This can save energy not only in terms of power consumed by the video card, but it will also lead to decreased heat generation, which can save money in terms of cooling costs. Surely though overall system health is impacted when less heat is dumped into your chassis. Kyle is using Radeon HD 7970 CrossFireX now and is singing its praises in terms of temperatures in his office coming from the GTX 580 SLI configuration.

The Radeon HD 7970 GPU itself is comprised of 4.32 billion transistors packed into 2048 stream processors with a clock speed of 925MHz. There are 128 texture units, 128 Z/stencil units, and 32 ROPs. That is a 33% increase in stream processors and texture units compared to the Radeon HD 6970, but the same number of ROP. Even so, optimizations and clock speed increases should result in more efficient rasterization.

The Radeon HD 7970 is designed to be paired with 3GB of GDDR5 memory on a 384-bit bus, running at 1375MHz for a 5.5Gbps data rate and a maximum theoretical bandwidth of 264GB per second. In spite of its increased capacity and its performance improvements, the Radeon HD 7970 shares the same 250W maximum board power rating as the HD 6970.

GIGABYTE Radeon HD 7970

The GV-R797OC-3GD is GIGABYTE's first overclocked video card in the HD 7000 series. It is designed to give a small performance boost Out-of-Box without the user needing to change anything. AMD's reference Radeon HD 7970 design has clock speeds set to 925MHz on the core and 1375MHz on the memory. GIGABYTE factory overclocked this video card to 1000MHz on the core, and left the memory unchanged. And from what we have seen in previous testing, memory bandwidth has not been a bottleneck at stock clocks for most configurations.

GIGABYTE loaded this custom video card up with its Ultra Durable VGA components. These include first tier Samsung and Hynix memories, high quality capacitors, ferrite chokes, and MOSFETs. Together these components combine for several benefits for the video card. GPU temperatures will be lower, it will provide for better overclocking ability, and will improve power efficiency which can increase performance.

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GIGABYTE's most unique feature on this video card is its custom cooling system, the "Windforce 3X." The Windforce 3X cooling system has a few key features. It starts on the GPU where the most heat is shed. Contacting the GPU are three 8mm copper heat pipes which spread through the heatsink directly over the GPU, and to two other elevated heatsinks. The heatsink directly contacting the GPU has another feature called "Triangle Cool." The three copper pipes run through this triangle shaped heatsink. This angle on the heatsink helps direct airflow from the fans towards the top and bottom of the video card, instead of blowing directly on to the PCB.

These heatsinks are built with very thin fins, which allow heat to come off the copper heat pipes and spread across the surface of each fin. The heat is removed from the fins by the Windforce 3X's, three ultra quiet PWM fans. And when we say ultra quiet, we mean nearly silent. These are set on a small, alternating inclines that helps reduce air turbulence and reduce noise. Each fan has several sharp, smooth blades that help cut through air and reduce wind resistance providing the cooling we want, without the noise we dread.

The GIGABYTE Radeon HD 7970 model GV-R797OC-3GD is available on Newegg for $609.99 plus shipping and handling. It is currently in a three way tie for the second fastest factory overclocked Radeon HD 7970 on the market (with ASUS and XFX) with MSI in first place having a 1010MHz core clock.

GIGABYTE Radeon HD 7970 Pictures

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GIGABYTE sent us this video card before the packaging was finished. We don't have a box or the packaging material to show you, but all the included parts are indicated on the website. GIGABYTE's website has listed that the video card comes with a CrossFireX bridge, a 6-pin and 8-pin auxiliary power connector, and driver installation CD.

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The front of the GIGABYTE GV-R797OC-3GD features a polished, black plastic cover that serves to house the 3 fans and cover the heatsink. The gloss gives it a nice sleek look. Although it is thin and light weight, it feels extremely durable and does not have any issue handling pressure in our experience.

You can see underneath the black cover that the heatsink spans the entire length of the video card. The far left and right parts of the heatsink are also elevated which allows for quicker heat spread and dissipation.

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On the I/O panel there are four ports. These include two mini-DP ports, a DVI-D connector, and one HDMI connector. The power connectors are on top of the video card, and require a 6-pin and 8-pin PCI-e power adapter. The GIGABYTE Radeon HD 7970 is roughly .5 inches smaller than a reference Radeon HD 7970 in each dimension, lending to its custom PCB nature. The video cards measurements are 10.5 inches in Length, 1.5 inches Wide, and 4.5 inches in Height.