Five Radeon HD 7970 3 GB Cards, Overclocked And Benchmarked

Gigabyte GV-R797OC-3GD

Gigabyte’s flagship Radeon HD 7970-based board employs a custom black PCB. Measuring 10.5” long, 4.75” tall, and 1.5” thick (not including the bezel), and weighing 1 lb 10.6 oz, this is the smallest and lightest card in our round-up. At press time, the GV-R797OC-3GD sells for an even $500 bucks on Newegg.

This card boasts a core clock of 1000 MHz core and memory running at 1375 MHz; that’s a 75 MHz GPU boost complemented by memory running at AMD's reference specification. Also like the reference model, Gigabyte's R797OC-3GD requires one six-pin and one eight-pin auxiliary power connector.

At first glance, this card's cooler appears to be fairly typical of what we've seen from Gigabyte in the past, with three 80 mm axial fans blowing over a trio of 8 mm heat pipes, all covered in a plastic shroud. The company claims that a new heat sink structure minimizes turbulence between the fans and provides better cooling efficiency. Of course, that sounds nice, but we need to put it through our test regimen in order to gauge the true improvement.

Gigabyte employs the same dual-link DVI, HDMI, and twin mini-DisplayPort outputs as AMD's reference design.

The company includes a CrossFire bridge, a DVI-to-VGA adapter, a dual four-pin Molex-to-six-pin power adapter, dual four-pin Molex-to-eight-pin power adapter, a driver disk, and a user guide.

Gigabyte covers the basics; however, we think that all Radeon HD 7970s should come with at least one mini-DisplayPort-to-DVI and one HDMI-to-DVI adapter for the folks interested in exploiting Eyefinity on the desktop. DisplayPort and HDMI are both less prevalent in that space.

Overclocking Gigabyte's R797OC-3GD

Gigabyte relies on AMD's Catalyst Control Center’s Overdrive feature for overclocking, though it enjoys an elevated 1200 MHz core and 1600 MHz memory limit.

MSI’s vendor-agnostic Afterburner software is even more generous in its ceilings, facilitating 1800 and 2475 MHz core and memory limits, with a voltage slider that tops out at 1.3 V.

We were able to stably overclock our sample to 1200 MHz and 1600 MHz for the core and memory, respectively, using a 1.25 V setting.

  • aznshinobi
    I need a new pair of pants. Definitely graphics card eye candy. Specially the Sapphire one IMO. Do I hear giveaway THG?
  • schnitter
    I need to replace my 5870 HD I bought over 3 years ago. I can still play any game on HIGH at 1080p, but I want ULTRA on BF3 and Max Payne 3.

    Lets hope the 680 GTX becomes available to see what price these AMD cards end up at. I like AMD and how they don't rebrand their cards like nVidia, but $20 cheaper than 680 GTX is not cheap enough to sway me that way.
  • hellfire24
    why a reference card(visiontek 7970) with non reference competitors?
    i am impressed with HIS IceQ X2 Turbo X but still MSi lightning is my favorite.they have beefier VRMs,great cooling and are overclocking beasts.

  • confish21
    Nice write up! Really helps when trying to peg down a card. Will be revisiting alot!
  • The gigabyte card pcb was BLUE, not BLACK :(
  • nekromobo
    visiontek for "Particularly at its modest $279 price."

    $379 or $479??
  • blazorthon
    nekromobovisiontek for "Particularly at its modest $279 price." $379 or $479??
    $479.99 (USD) is more or less the cheapest price point for any Radeon 7970.
  • weatherdude
    Cool review. It'd be nice if SI units were included in the weights and lengths though. Guess I'll have to do a little math. It's very nice to know that the non-reference coolers are much quieter (excluding Gigabyte's) than the original design.

    Let's see some typos:

    In the 'Test System Setup And Benchmarks' page in the Operating System row it is written as Microsoft Windows 7 x6. I assume it's supposed to be x64.

    In the first paragraph of the 'Sapphire HD 7970 OC' page the card is described as "HD 7970 PC".
  • Reynod
    Good review Don.

    I agree with your first and second choices ... well thought out.

  • cangelini
    Fixed the typos; thanks weatherdude and nekromobo.