AMD Radeon HD 7970 GHz Edition Review: Give Me Back That Crown!

Is An Overclocked Radeon HD 7970 Greater Than GeForce GTX 680?

Can you believe the Radeon HD 7970 was introduced six months ago? In those 180 days, we’ve seen AMD claim the single-GPU performance crown, flesh out an entire family of graphics cards based on its capable GCN architecture, and then lose its fastest-in-the-world title to Nvidia’s GeForce GTX 680. I’m working on a script for the movie.

Along the way, though, we’ve wondered about the company’s approach to pricing. Even after Nvidia launched a faster, less expensive card, AMD kept selling its Radeon HD 7970 for $550. It eventually shaved off $70, only to see the competition kick out an even cheaper board (GeForce GTX 670) able to rout the 7970 in most games.

At no point was AMD’s flagship ever a bad card, though. Its dominance was simply contested quickly—and frustratingly—by a competing piece of hardware suffering such poor availability that you had to sign up for notifications just to catch it in stock. Although 680s are in stock now, as recently as a couple of weeks ago they were mostly a threat on paper. But the GeForce GTX 670 has always been a lot more accessible at $400, putting the Radeon HD 7970 under significant pressure. Certain 7970s are even down as low as $450.

To the point, with the maturation of TSMC’s 28 nm manufacturing process, AMD is discovering that a greater number of its Tahiti GPUs are running stably at higher core clock rates. Now, we already knew that the Radeon HD 7900s overclocked well. But rather than leaving extra performance on the table for enthusiasts to exploit on their own time, the company is unveiling a Radeon HD 7970 GHz Edition card that purportedly one-ups Nvidia’s GTX 680 and gives AMD a reason to push prices back up.

Meet The Radeon HD 7970 GHz Edition

Physically, this is the Radeon HD 7970 you already know. Put AMD’s reference GHz Edition card next to the one launched six months ago and you can’t tell them apart. What few differences there are all materialize under the card’s 11”-long fan shroud.

Most obvious is a higher core clock rate. Officially, AMD lists it at 1000 MHz—a bump up from the original version’s 925 MHz frequency. But it also enables a higher 1050 MHz P-state that the GPU favors when thermal headroom allows. AMD is marketing this combination of clock rates as PowerTune with Boost.

If you’re not already familiar with what PowerTune is or how it works, I break it down in my Radeon HD 6970 and 6950 review. Basically, though, AMD confirmed for us that PowerTune with Boost is the same exact thing, plus the ability to dynamically increase voltage. The company says its 1 GHz clock is fixed, and altering Overdrive’s frequency slider only changes the maximum boost level.

But it seems like you could also describe the 7970 GHz Edition as a 1.05 GHz card that, subjected to a synthetic power load like FurMark, drops 50 MHz and some voltage to not violate its TDP. After all, that’s what PowerTune has done for a year and a half.

The other performance enhancement comes courtesy of faster memory. Back when AMD launched the Radeon HD 7970, it “only” had access to 1375 MHz GDDR5 modules. On a nice, wide 384-bit bus, they were good for 264 GB/s of aggregate bandwidth. Now it’s using 3 GB of 1500 MHz modules on the same bus to push 288 GB/s.

Swipe to scroll horizontally
Header Cell - Column 0 Radeon HD 7970 GHz EditionRadeon HD 7970GeForce GTX 680
Stream processors204820481536
Texture Units128128128
Full Color ROPs323232
Graphics Clock1000 MHz Base / 1050 MHz Boost925 MHz1006 MHz
Texture Fillrate134.4 Gtex/s118.4 Gtex/s128.8 Gtex/s
Memory Clock1500 MHz1375 MHz1502 MHz
Memory Bus384-bit384-bit256-bit
Memory Bandwidth288 GB/s264 GB/s192.3 GB/s
Die Size365 mm2365 mm2294 mm2
Transistors (Billion)4.314.313.54
Process Technology28 nm28 nm28 nm
Power Connectors1 x 8-pin, 1 x 6-pin1 x 8-pin, 1 x 6-pin2 x 6-pin
Maximum power (TDP)250 W250 W195 W
Price$500 MSRP$450 Street~$520 Street

AMD acknowledges that the Tahiti GPU itself is exactly the same. If you want the skinny on that, feel free to reference back to our Radeon HD 7970 launch coverage. Everyone else, let’s move on to a deeper analysis of PowerTune with Boost.

Chris Angelini
Chris Angelini is an Editor Emeritus at Tom's Hardware US. He edits hardware reviews and covers high-profile CPU and GPU launches.
  • esrever
    50 mhz boosts are kinda low imo
  • Darkerson
    My only complaint with the "new" card is the price. Otherwise it looks like a nice card. Better than the original version, at any rate, not that the original was a bad card to begin with.
  • mayankleoboy1
    Thanks for putting my name in teh review :D

    now if only you could bold it :lol:
  • wasabiman321
    Great I just ordered a gtx 670 ftw... Grrr I hope performance gets better for nvidia drivers too :D
  • mayankleoboy1
    nice show AMD !

    with Winzip that does not use GPU, VCE that slows down video encoding and a card that gives lower min FPS..... EPIC FAIL.
    or before releasing your products, try to ensure S/W compatibility.
  • hellfire24
    not trying to be a fanboy but "Still GTX 670 gives you best BANG FOR DA BUCK!"
  • vmem
    jrharbortTo me, increasing the memory speed was a pointless move. Nvidia realized that all of the bandwidth provided by GDDR5 and a 384bit bus is almost never utilized. The drop back to a 256bit bus on their GTX 680 allowed them to cut cost and power usage without causing a drop in performance. High end AMD cards see the most improvement from an increased core clock. Memory... Not so much.Then again, Nvidia pretty much cheated on this generation as well. Cutting out nearly 80% of the GPGPU logic, something Nvidia had been trying to market for YEARS, allowed then to even further drop production costs and power usage. AMD now has the lead in this market, but at the cost of higher power consumption and production cost.This quick fix by AMD will work for now, but they obviously need to rethink their future designs a bit.
    the issue is them rethinking their future designs scares me... Nvidia has started a HORRIBLE trend in the business that I hope to dear god AMD does not follow suite. True, Nvidia is able to produce more gaming performance for less, but this is pushing anyone who wants GPU compute to get an overpriced professional card. now before you say "well if you're making a living out of it, fork out the cash and go Quadro", let me remind you that a lot of innovators in various fields actually do use GPU compute to ultimately make progress (especially in academic sciences) to ultimately bring us better tech AND new directions in tech development... and I for one know a lot of government funded labs that can't afford to buy a stack of quadro cards
  • andrewcarr
    So happy :)
  • DataGrave
    Nvidia has started a HORRIBLE trend in the business that I hope to dear god AMD does not follow suite.
    100% acknowledge

    And for the gamers: take a look at the new UT4 engine! Without excellent GPGPU performace this will be a disaster for each graphics card. See you, Nvidia.
  • cangelini
    mayankleoboy1Thanks for putting my name in teh review now if only you could bold it;-)
    Excellent tip. Told you I'd look into it!