AMD: Volcanic Islands R1100/1200 (8***/9*** series) Speculation/ Rumour Thread

I'd really like to hear "proper sources" for this since there's only one BIOS out there in TPU database which has any mentions of XT2 for R9 280X, and even it says XT2_XTL, the rest say all XTL or nothing at all.

So at least IMO everything points to all the R9 280Xs already using XTL, and like I think Dave mentioned here, the differences between XT2 and XTL and Pitcairn and Curacao are simply in the TSMC process improvements which could be used with the 'new revisions' but weren't in use on the older chips
XTL also introduces a temperature dependent clock-rate on Tahiti:
http://ht4u.net/reviews/2013/amds_r...270x_und_280x_und_r7_260x_im_test/index19.php
With 80°C in Furmark the card lowers clock to 501MHz. After a while it cools down to 78°C and starts again to boost (900-1050MHz).
 
Is it really fair to make such claims?

Another week without launching the 290X would be another week with nVidia selling the GTX 780 for $650, and another week's worth of potential customers willing to buy a graphics card for the coming holiday season.

If you know that something new is going out and hopefully making prices fall, you mostly would like to wait before buying anything
 
You're assuming that the next high-end GPU from AMD needs a lot more than 320GB/s. There's a good chance it won't.

Titan still sits at the top with only 288GB/s, and the GTX 680 still does very well with just 192GB/s.
There's no such thing as "need" and "doesn't need" when it comes to BW. Almost all games will present some fraction of the rendering workload that will be memory bandwidth limited, and that fraction will be sped up by faster memory. GK110 and GK104 left performance on the table by not more BW, but of course BW isn't free either.

Moreover, many recent games/benchmarks don't see much of a difference between the GTX 670 and the GTX 660 Ti, where both use the GK104 with one SMX disabled but the later has 25% less memory bandwidth and ROPs.
You're right about this being a good way to evaluate bandwidth needs of games, but you're wrong in saying that there isn't much difference. Take a look at the performance difference between the stock 670 and stock 660 Ti:
http://www.anandtech.com/show/6159/the-geforce-gtx-660-ti-review
There's a pretty substantial gap in all games except Portal 2.

Note that if the 670 is 10% faster, it is BW/ROP limited ~30% of the time. For example, if game's rendering time averaged 20ms (50 fps) on the 670, and 6ms was BW or ROP limited, then the latter workload would take 8ms on the 660 Ti, and thus take 22ms (45.5 fps) to render, making the 670 10% faster.

In Anand's review, several games exceeded a 10% drop. Batman looks like it's 75% BW limited.
 
Where are you hearing this? This is completely false.

It's the same story over and over with AMD and new toy's, "not in stock". Here in the Netherlands there where a handfull, but now empty shelves like it use to be, same goes for Germany. The UK has an handfull, nothing more...
 
If you know that something new is going out and hopefully making prices fall, you mostly would like to wait before buying anything

Not everyone plays the waiting game right. In fact, I wonder if many people do it at all.


There's no such thing as "need" and "doesn't need" when it comes to BW.

There's a factor of balance, just as in everything else. At a certain level of IQ/resolution, increasing memory bandwidth may result in residual improvements or no improvement at all. If I want to play game X at 1080p with GPU Y there can be situations where I don't need the version with higher memory bandwidth.



You're right about this being a good way to evaluate bandwidth needs of games, but you're wrong in saying that there isn't much difference. Take a look at the performance difference between the stock 670 and stock 660 Ti:
http://www.anandtech.com/show/6159/the-geforce-gtx-660-ti-review
There's a pretty substantial gap in all games except Portal 2.

For starters, do they even sell non-"overclocked" GTX 660 Ti cards these days? The approximation to the GTX670 was made from day one because AFAIK most 660 Ti being sold are factory overclocked.


Anyways, for 1200p (because 1080p+1200p should be the overwhelming majority for gamers today) and all games maxed out:
Crysis Warhead: 20% difference
Metro 2033: 13% difference
Dirt 3: 11% difference
Shogun 2: 6% difference
Arkham City: 19% difference
Portal 2: 2% difference
BF3: 16% difference
Skyrim: 8% difference
Civ V: 10% difference

For 25% more ROPs and memory bandwidth, only 3 of those games show a substantial difference.
Regardless, all these games are playing at over 50/60FPS so there isn't much difference. In some of them, there's no difference at all..

Another good example are the GTX 770 vs. GTX 680 reviews. Despite the ~14% memory bandwidth advantage (and marginally higher clocks), you won't see more than a 5% bump in performance, if at all.


Note that if the 670 is 10% faster, it is BW/ROP limited ~30% of the time.
What?!?





Whatever.. the point was - and still is - higher memory bandwidth for the R9 290X may not be needed at all. Not for that card or even its successor.
Taking a look at the 290X with overclock shows exactly what I'm saying.

290X with 5GT/s memory, 320GB/s:
uGBMCfs.jpg


290X with memory overclocked to 6.2GT/s, 397GB/s:
8zc2oTS.jpg




Performance boost for 20% higher memory bandwidth is 0,004%.
Yeah, totally worth it...
 
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If you going from 75 BW to 100 BW (+33%) results in going from 100 perf to 133 perf, then you can conclude that, 100% of the time, your BW was the bottleneck that was limiting perf. Similarly, if the perf only went up from 100 to 110, the BW was the bottleneck ~30% of the time.
 
290Xs at newegg were sold out in only couple of hours and since then there has been nothing new. That fud is true

You would think by now that people would understand that a product being sold out shortly after launch only means that demand greatly outpaces supply.

It does NOT say anything about how many cards were released, even remotely.

If 100,000 customers of X shop wanted Y product at launch...

1. With 100 of Y product allocated to X shop, they would be sold out.
2. With 1,000 of Y product allocated to X shop, they would be sold out.
3. With 10,000 of Y product allocated to X shop, they would be sold out.
4. Etc.

Heck, if 10 million people worldwide wanted to buy X product, it would be sold out whether 10,000 of X product was released or 1 million of X product was released.

So, just like with the launch of 5870, 6970, 7970 for AMD and 580, 680 for Nvidia, being sold out for weeks/months after launch doesn't say one single bit about how many video cards were actually supplied. The only thing it says is that more people wanted one than AMD or Nvidia could produce for those first weeks/months.

Regards,
SB
 
At a certain level of IQ/resolution, increasing memory bandwidth may result in residual improvements or no improvement at all.
Really? Then why bother increasing performance at all? Or do you have some way of telling the difference between 10% difference from BW and 10% difference from the GPU?
For starters, do they even sell non-"overclocked" GTX 660 Ti cards these days?
Irrelevant. They sell overclocked 670's, too.
For 25% more ROPs and memory bandwidth, only 3 of those games show a substantial difference.
You're not very good at counting.
Any reason why you snipped out the part where I meticulously explained the mathematics behind that?
Performance boost for 20% higher memory bandwidth is 0,004%.
3DMark is not a game.
 
Once the 290 is released, I'd expect demand for the 290X to drop and for them to be available again.

That's pretty typical isn't it? When the GTX670 came out it almost defeated the purpose of the GTX680. Even more so with the GTX780 vs Titan.

The real sweet spot right now is in the ~$210 range, where I scored an HD7950 Boost with 3 friggin awesome games at regular price on Newegg few weeks ago. The prices have gone up some since then, but if you shop around you can still get close to that.

Get'm while they're hot!
 
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