AMD Radeon 7000-Series 28nm (Southern Islands) | 7990 7970 7870 7770 | Discussion

[videoclone]

Southern Islands is a codename for the new AMD graphics architecture ( GCN - Graphics Core Next ) that is replacing VLIW4 used in the previous AMD HD6000 series of graphics cards. Southern Islands graphics processors will be manufactured with a 28nm process. The new architecture is expected to have significantly increased computational efficiency and higher double-precision FP performance-per-watt. Together with the promised enhanced programmability, Southern Islands should be more efficient for GPGPU tasks. Southern Islands based gaming graphics accelerators will be known as the AMD Radeon 7000 series.

AMD GPU Specification

AMD Radeon HD 7970
Stream Processors 2048
Texture Units 128
ROPs 32
Core Clock 925MHz
Memory Clock 1.375GHz (5.5GHz effective) GDDR5
Memory Bus Width 384-bit
Frame Buffer 3GB
FP64 1/4
Transistor Count 4.31B
Manufacturing Process TSMC 28nm
Price Point $549
_______________________________________

News:
AMD Radeon HD7970 Full review http://www.anandtech.com/show/5261/amd-radeon-hd-7970-review

 

[Lonyo]

That's a lot of memory and a lot of memory bandwidth over the 6900 series if true.

Shame they don't have anything about power use though, since that's pretty useful information.

Also you might want to put the source in the title if there is one...

 

[videoclone]

Few places have this now and will be keeping an eye out for the anandtech write up on the "Graphics Core Next" (GCN) Architecture

 

[RavenSEAL]

But can it run Crysis?

 

[-Slacker-]

Looks like the old leaks had the specs spot on, except for the type and speed of the vram.

But I hope to god those prices don't reflect actual performance, just like the 4800 series didn't...

 

[WMD]

OMG! Finally we stop seeing 256Bit DDR5! Not too happy about the price though.

 

[lavaheadache]

I have the money saved under my 3d ir reciever... Ready for release. Too bad I prefer Nvidia solely cause my wifey bought me the 3d setup for Christmas last year.

 

[lavaheadache]

But can it run Crysis?

Probably not... lol. 2007 still haunts us in the form of Crysis

 

[-Slacker-]

Looking at the specs again, and assuming that, at least, a GCN core isn't much slower that a VLIW4 SP, I can't imagine how the HD 7970 would only fall somewhere on gtx 580 performance levels; Either they are going for very aggressive prices again to gain back market share, or the estimated prices are wrong...

 

[Chinoman]

If GCN is anything like Cayman, I can see this thing being ~= GTX 590 in performance.

 

[SlowSpyder]

Looks like the old leaks had the specs spot on, except for the type and speed of the vram.

But I hope to god those prices don't reflect actual performance, just like the 4800 series didn't...

Looking at the specs again, and assuming that, at least, a GCN core isn't much slower that a VLIW4 SP, I can't imagine how the HD 7970 would only fall somewhere on gtx 580 performance levels; Either they are going for very aggressive prices again to gain back market share, or the estimated prices are wrong...

What's wrong with these prices? If correct, AMD is clearly pricing it higher than what the 6970 launched at (and very close to what the GTX580 sells at). It seems to me, that if anything, they expect this to be the fastest card for a while, and probably pretty competitive with Nvidia's fastest single GPU.

 

[-Slacker-]

As I said, I'm not assuming out of hand that just because it's priced close to the gtx 580 it won't be significantly faster, since I have already acknowledged a scenario like the one back in 2008 when the 4800s were twice as cheap as the high end gtx 200s at launch but kept up in performance.

I hope that's the case if the prices are to be believed.

 

[Rhezuss]

Will the 7950 unlock?

 

[ArizonaSteve]

Here's hoping that one GCN core >> one VLIW4 core.

Looks like 7950 will be the sweet spot.

Just curious, seeing that most games are 32 bit and the 7990 will arrive with 6GB of RAM, will it be impossible to make use of all the VRAM when playing 32 bit games? Or is the VRAM addressed by the (64 bit) video driver in its own address space?

 

[SlowSpyder]

As I said, I'm not assuming out of hand that just because it's priced close to the gtx 580 it won't be significantly faster, since I have already acknowledged a scenario like the one back in 2008 when the 4800s were twice as cheap as the high end gtx 200s at launch but kept up in performance.

I hope that's the case if the prices are to be believed.

Maybe I'm missing what you are saying, then. I don't think this is overly aggressive pricing. I believe AMD is pricing these right in line with what the expected performance will be. They have to price them at what the market will allow... selling these for $250 and making a penny of profit won't help them, even if they sell 10 million a quarter. Likewise, pricing them at $10k and selling 500 a quarter won't do much for them. I think the 7970 will be much faster than the GTX580, and be priced pretty close to what we have seen top single GPU parts sell for lately. I'm sure AMD expects price cuts from Nvidia if the GTX5xx cards are what Nvidia has for the immediate future, or they expect Nvidia to have their next gen out in the not too distant future.

At any rate, the 7950 may be my next upgrade... I am looking to get my power use down to respectable levels from two 5870's, and at 1920x1200 1GB is going to be a limiting factor soon.

 

[Borealis7]

Wow, looks expensive...I hope its worth it.

are we sure we can compare GCN cores to VLIW4 cores? it could also be that 2048 GCN cores will roughly equal 1600-1800 VLIW4 cores

 

[Olikan]

Here's hoping that one GCN core >> one VLIW4 core.

it won't be in performance\mm². VLIW will always be better. Fixed instructions are always better for that.

But, fixed instructions are, well, fixed....so a GCN may actually be better, in things that a vliw don't, thus increasing the performance.

 

[toyota]

how do you get 64 and 60 ROPs with 384 bit?

 

[s44]

With these core numbers are we sure they're even using GCN on these products?

 

[tviceman]

Wow, looks expensive...I hope its worth it.

are we sure we can compare GCN cores to VLIW4 cores? it could also be that 2048 GCN cores will roughly equal 1600-1800 VLIW4 cores

I don't think it can be compared accurately with so many unknowns. Just like Nvidia's cores aren't comparable to AMD's, this is a whole new architecture and has many unknowns. AMD is moving in the same direction as Nvidia now with general GPU capabilities, so my guess without any other information, is that GCN cores will be more versatile but slightly less powerful than VLIW.

 

[superccs]

Looks enticing. I wouldn't mind AMD shipping me a 7950. Wonder what the 7800's will be like.

 

[HurleyBird]

Memory Bus Width 384-bits
ROPs 64

...

 

[tw1164]

Looks enticing. I wouldn't mind AMD shipping me a 7950. Wonder what the 7800's will be like.

When are they rumored to come out?

 

[Phynaz]

I'm more interested in low power.

Is it confirmed the 7xxx series is GCN? I thought GCN was a ways away yet.

 

[Deleted member 4644]

Assuming the various shaders/processors perform similarly to older units, about how fast might this be?

Ripped this form HardForums:

7970XT against 6970 would be:
33% More Shaders
33% More Texture Units
13,6% Higher Clock Speed
65% Higher Memory Bandwidth
51% more Gflops

That looks pretty decent.