AMD Radeon HD 7970 Review: 28nm And Graphics Core Next, Together As One
by Ryan Smith on December 22, 2011 12:00 AM EST- Posted in
- GPUs
- AMD
- Radeon
- ATI
- Radeon HD 7000
While AMD and NVIDIA are consistently revising their GPU architectures, for the most part the changes they make are just that: revisions. It’s only once in a great while that a GPU architecture is thrown out entirely, which makes the arrival of a new architecture a monumental occasion in the GPU industry. The last time we saw this happen was in 2006/2007, when unified shaders and DirectX 10 lead to AMD and NVIDIA developing brand new architectures for their GPUs. Since then there have been some important revisions such as AMD’s VLIW4 architecture and NVIDIA’s Fermi architecture, but so far nothing has quite compared to 2006/2007, until now.
At AMD’s Fusion Developer Summit 2011 AMD announced Graphics Core Next, their next-generation GPU architecture. GCN would be AMD’s Fermi moment, where AMD got serious about GPU computing and finally built an architecture that would serve as both a graphics workhorse and a computing workhorse. With the ever increasing costs of high-end GPU development it’s not enough to merely develop graphics GPUs, GPU developers must expand into GPU computing in order to capture the market share they need to live well into the future.
At the same time, by canceling their 32nm process TSMC has directed a lot of hype about future GPU development onto the 28nm process, where the next generation of GPUs would be developed. In an industry accustomed to rapid change and even more rapid improvement never before have GPU developers and their buyers had to wait a full 2 years for a new fabrication process to come online.
All of this has lead to a perfect storm of anticipation for what has become the Radeon HD 7970: not only is it the first video card based on a 28nm GPU, but it’s the first member of the Southern Islands and by extension the first video card to implement GCN. As a result the Radeon HD 7970 has a tough job to fill, as a gaming card it not only needs to deliver the next-generation performance gamers expect, but as the first GCN part it needs to prove that AMD’s GCN architecture is going to make them a competitor in the GPU computing space. Can the 7970 do all of these things and live up to the anticipation? Let’s find out…
| AMD GPU Specification Comparison | ||||||
| AMD Radeon HD 7970 | AMD Radeon HD 6970 | AMD Radeon HD 6870 | AMD Radeon HD 5870 | |||
| Stream Processors | 2048 | 1536 | 1120 | 1600 | ||
| Texture Units | 128 | 96 | 56 | 80 | ||
| ROPs | 32 | 32 | 32 | 32 | ||
| Core Clock | 925MHz | 880MHz | 900MHz | 850MHz | ||
| Memory Clock | 1.375GHz (5.5GHz effective) GDDR5 | 1.375GHz (5.5GHz effective) GDDR5 | 1.05GHz (4.2GHz effective) GDDR5 | 1.2GHz (4.8GHz effective) GDDR5 | ||
| Memory Bus Width | 384-bit | 256-bit | 256-bit | 256-bit | ||
| Frame Buffer | 3GB | 2GB | 1GB | 1GB | ||
| FP64 | 1/4 | 1/4 | N/A | 1/5 | ||
| Transistor Count | 4.31B | 2.64B | 1.7B | 2.15B | ||
| Manufacturing Process | TSMC 28nm | TSMC 40nm | TSMC 40nm | TSMC 40nm | ||
| Price Point | $549 | $350 | $160 | - | ||
The Radeon HD 7970 is a card of many firsts. It’s the first video card using a 28nm GPU. It’s the first card supporting Direct3D 11.1. It’s the first member of AMD’s new Southern Islands Family. And it’s the first video card implementing AMD’s Graphics Core Next architecture. All of these attributes combine to make the 7970 quite a different video card from any AMD video card before it.
Cutting right to the chase, the 7970 will serve as AMD’s flagship video card for the Southern Islands family. Based on a complete AMD Tahiti GPU, it has 2048 stream processors organized according to AMD’s new SIMD-based GCN architecture. With so many stream processors coupled with a 384bit GDDR5 memory bus, it’s no surprise that Tahiti is has the highest transistor count of any GPU yet: 4.31B transistors. Fabricated on TSMC’s new 28nm High-K process, this gives it a die size of 365mm2, making it only slightly smaller than AMD’s 40nm Cayman GPU at 389mm2.
Looking at specifications specific to the 7970, AMD will be clocking it at 925MHz, giving it 3.79TFLOPs of theoretical computing performance compared to 2.7TFLOPs under the much different VLIW4 architecture of the 6970. Meanwhile the wider 384bit GDDR5 memory bus for 7970 will be clocked at 1.375GHz (5.5GHz data rate), giving it 264GB/sec of memory bandwidth, a significant jump over the 176GB/sec of the 6970.
These functional units are joined by a number of other elements, including 8 ROP partitions that can process 32 ROPs per clock, 128 texture units divided up among 32 Compute Units (CUs), and a fixed function pipeline that contains a pair of AMD’s 9th generation geometry engines. Of course all of this hardware would normally take quite a bit of power to run, but thankfully power usage is kept in check by the advancements offered by TSMC’s 28nm process. AMD hasn’t provided us with an official typical board power, but we estimate it’s around 220W, with an absolute 250W PowerTune limit. Meanwhile idle power usage is looking particularly good, as thanks to AMD's further work on power savings their typical power consumption under idle is only 15W. And with AMD's new ZeroCore Power technology (more on that in a bit), idle power usage drops to an asbolutely miniscule 3W.
Overall for those of you looking for a quick summary of performance, the 7970 is quite powerful, but it may not be as powerful as you were expecting. Depending on the game being tested it’s anywhere between 5% and 35% faster than NVIDIA’s GeForce GTX 580, averaging 15% to 25% depending on the specific resolution in use. Furthermore thanks to TSMC’s 28nm process power usage is upwards of 50W lower than the GTX 580, but it’s still higher than the 6970 it replaces. As far as performance jumps go from new fabrication processes, this isn’t as big a leap as we’ve seen in the past.
In a significant departure from the launch of the Radeon HD 5870 and 4870, AMD will not be pricing the 7970 nearly as aggressively as those cards with its launch. The MSRP for the 7970 will be $550, a premium price befitting a premium card, but a price based almost exclusively on the competition (e.g. the GTX 580) rather than one that takes advantage of cheaper manufacturing costs to aggressively undercuts the competition. In time AMD needs to bring down the price of the card, but for the time being they will be charging a price premium reflecting the card’s status as the single-GPU king.
For those of you trying to decide whether to get a 7970, you will have some time to decide. This is a soft launch; AMD will not make the 7970 available until January 9th (the day before the Consumer Electronics Show), nearly 3 weeks from now. We don’t have any idea what the launch quantities will be like, but from what we hear TSMC’s 28nm process has finally reached reasonable yields, so AMD should be in a better position than the 5870 launch. The price premium on the card will also help taper demand side some, though even at $550 this won’t rule out the first batch of cards selling out.
Beyond January 9th, AMD as an entire family of Southern Islands video cards still to launch. AMD will reveal more about those in due time, but as with the Evergreen and Northern Islands families AMD has a plan to introduce a number of video cards over the next year. So 7970 is just the beginning.
| Winter 2011 GPU Pricing Comparison | |||||
| AMD | Price | NVIDIA | |||
| $750 | GeForce GTX 590 | ||||
| Radeon HD 6990 | $700 | ||||
| Radeon HD 7970 | $549 | ||||
| $500 | GeForce GTX 580 | ||||
| Radeon HD 6970 | $350 | GeForce GTX 570 | |||
| Radeon HD 6950 2GB | $250 | ||||
| $240 | GeForce GTX 560 Ti | ||||
| Radeon HD 6870 | $160 | ||||
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292 Comments
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RussianSensation - Saturday, January 14, 2012 - link
BF3 is not a 2012 game.......Also, most of us have been gaming on our older cards. Who in the world who has a previous high-end card is going to drop $600 for BF3 alone? No thanks.
SSIV - Saturday, February 18, 2012 - link
Since there's a new driver out for there cards we can now regard these results with a grain of salt. Revise the benchmarks!DaOGGuru - Thursday, March 1, 2012 - link
I don't know why people keep forgeting about the 560ti 2win. Yes I said 2win = 2 560ti processors on one card. It still kills the 7970 numbers in BF3 by 20Fps. and is same price. It also beats the 580 and is cheaper. It's a single card with 50amp min. draw and it will smoke anything except 590 and the 6990...http://www.guru3d.com/article/evga-geforce-gtx-560...
CeriseCogburn - Thursday, March 8, 2012 - link
Oh, right, well this isn't an nvidia card review, so we won't hear from 50 posts about how some CF (would be SLI of course in this case) combo will whip the crap out of it in performance and price...You know ?
That's how it goes...
Usually the articel itself rages on about how some amd CF combo is really so much good and better and blah blah blah.... then the rpice perf, then the results - on and on and on ....
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The angry ankle biters are swarmed up on the under red dog radeon side...
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So you made a very good point, I'm just sorry it took 29 pages of reading to get to it, in it's glorious singularity.... you shouldn't strike out in independent thought like that it's dangerous.... not allowed unless the card being reviewed is an nvidia !!!!
DaOGGuru - Thursday, March 1, 2012 - link
oops... forgot to say look at previous post links BF3 rating for the 560ti 2win and compare to this charts 7970 fps. The 2win is pumping out @20 more FPS and is $50.00 - $100.00 cheaper than the 7970... lame.. ATi is still behind Nvidia but proud of it! lol They are just now catching up to Nvidia's tessellations and oh and AFTER they changed to a "cuda core copy" architecture and posting it as big news... Evga's older 560ti 2win still dusts it by 20FPS.. lame.DaOGGuru - Thursday, March 1, 2012 - link
sorry 10FPS not 20.. it's late.DaOGGuru - Thursday, March 1, 2012 - link
I don't get what's the hub-bub about the 7970.. sure it's the fastest single cpu;BUT, for $50.00-$100.00 less you can get the 560Ti 2win (dual cpu) that smokes the 7970 and the 2win PCB does have an SLI bridge and is cabapable of doing SLI to a second card but it's currently locked by Nvidia (see paragraph 3).Also, the 2win draws a min of only 50amps (way less than most sli configurations) 1. has a considerably lower noise dba, 2. runs cooler and with less power than almost all the high end cards and 3. will run 3 montiors in Nvidia 2D and 3D surround off a single card! 4.Will kill the GTX 580 by @33-23% (depending on review) 5. Will beat the 590 in some sample testing for TDP. And finally 6. will kill the 7970 by 10-20FPS in BF3 including by 10FPS in 1920x1200 4AA-16AF Ultra high mode. So, why have people forgotten the 2win? It's a singlecard, multi-GPU, full 3D/2D surround without a second card in SLI, $500.00USD beast !
OH and for those that say you can't SLI with a second 2win.... http://www.guru3d.com/article/evga-geforce-gtx-560... (this review states on conclusion page) > quote " you will have noticed there is a SLI connector on the PCB. Unfortunately you can not add a second card to go for quad-SLI mode. It's not a hardware limitation, yet a limitation set by NVIDIA, the GTX 560 Ti series is only allowed in 2-way SLI mode, which this card already is."
... So actually, the card is cabale 2card SLI but Nvidia for some (gosh aweful reason) won't let the dog off the chain. Probably because it will absolutely kill the need for a GTX580, 570, 560 Ti SLI configuration for ever!
Resources: (pay attention to BF3 FPS and compare to 7970 FPS in this article.)
http://www.anandtech.com/show/5048/evgas-geforce-g...
http://www.guru3d.com/article/evga-geforce-gtx-560...
Peace...
DaOGGuru - Thursday, March 1, 2012 - link
I don't get what's the hub-bub about the 7970.. sure it's the fastest single CPU; BUT, for $50.00-$100.00 less you can get the 560Ti 2win (dualCPU) that smokes the 7970 and the 2win PCB does have an SLI bridge and is capable of doing SLI to a second card but it's currently locked by Nvidia (see paragraph 3).Also, the 2win draws a min of only 50amps (way less than most sli configurations) 1. Has a considerably lower noise DBA, 2. runs cooler and with less power than almost all the high end cards and 3. Will run 3 monitors in Nvidia 2D and 3D surround off a single card! 4.Will kill the GTX 580 by @33-23% (depending on review) 5. Will beat the 590 in some sample testing for TDP. And finally 6. will kill the 7970 by 10-20FPS in BF3 including by 10FPS in 1920x1200 4AA-16AF Ultra high mode. So, why have people forgotten the 2win? It's a single card, multi-GPU, full 3D/2D surround without a second card in SLI, $500.00USD beast !
OH and for those that say you can't SLI with a second 2win.... http://www.guru3d.com/article/evga-geforce-gtx-560... (this review states on conclusion page) > quote " you will have noticed there is a SLI connector on the PCB. Unfortunately you cannot add a second card to go for quad-SLI mode. It's not a hardware limitation, yet a limitation set by NVIDIA, the GTX 560 Ti series is only allowed in 2-way SLI mode, which this card already is."
... So actually, the card is capable 2card SLI but Nvidia for some (gosh awful reason) won't let the dog off the chain. Probably because it will absolutely kill the need for a GTX580, 570, 560 Ti SLI configuration forever!
Resources: (pay attention to BF3 FPS and compare to 7970 FPS in this article.)
http://www.anandtech.com/show/5048/evgas-geforce-g...
http://www.guru3d.com/article/evga-geforce-gtx-560...
Peace...
CeriseCogburn - Thursday, March 8, 2012 - link
Ummm.... I read you, I see your frustration with all the posts - just refer to my one above there - you really should not be dissing the new amd like that - they like are 1st and uhh... nvidia is evil... so no comparisons like that are allowed when the fanboy side content is like 100 to 1....Now next nvidia card review you will notice a hundred posts on how this or that CF beats the nvidia in price perf and overall perf, etc, and it will be memorized and screamed far and wide...
Just like... your point "doesn't count", okay ?
It's best to ignore you GREEN fanboy types... ( yes even if you point out gigantic savings, or rather especially when you do...)
Thanks for waiting till page 30 - a wise choice.
CeriseCogburn - Sunday, March 11, 2012 - link
Southern Islands is a whole generation late. AMD promised us this SI in the last generation 6000 series. Then right before that prior release, they told us they had changed everything and 6000 was not Southern Islands anymore. LOLTalk about late - it's what two years late ?
Maybe it's three years....
In every case here, Nvidia beat them to the core architecture by two years. Now amd is merely late to the party crashing copycats....
That's late son, that's not original, that's not innovative, that's not superior, it's tag a long tu loo little sister style.