Monday, September 27th 2010
AMD Radeon HD 6700 Series ''Barts'' Specs Sheet Surfaces
Here is the slide we've been waiting for, the specs sheet of AMD's next-generation Radeon HD 6700 series GPUs, based on a new, radically redesigned core, codenamed "Barts". The XT variant denotes Radeon HD 6770, and Pro denotes HD 6750. AMD claims that the HD 6700 series will pack "Twice the Horsepower", over previous generation HD 5700 series. Compared to the "Juniper" die that went into making the Radeon HD 5700 series, Barts features twice the memory bandwidth thanks to its 256-bit wide high-speed memory interface, key components such as the SIMD arrays split into two blocks (like on Cypress), and we're now getting to learn that it uses a more efficient 4-D stream processor design. There are 1280 stream processors available to the HD 6770 (Barts XT), and 1120 stream processors to the HD 6750 (Barts Pro). Both SKUs use the full 256-bit memory bus width.
The most interesting specification here is the shader compute power. Barts XT churns out 2.3 TFLOP/s with 1280 stream processors, GPU clocked at 900 MHz, while the Radeon HD 5870 manages 2.72 TFLOP/s with 1600 stream processors, 850 MHz. So indeed the redesigned SIMD core is working its magic. Z/Stencil performance also shot up more than 100% over the Radeon HD 5700 series. Both the HD 6770 and HD 6750 will be equipped with 5 GT/s memory chips, at least on the reference-design cards, which are technically capable of running at 1250 MHz (5 GHz effective), though are clocked at 1050 MHz (4.20 GHz effective) on HD 6770, and 1000 MHz (4 GHz effective) on HD 6750. Although these design changes will inevitably result in a larger die compared to Juniper, it could still be smaller than Cypress, and hence, more energy-efficient.
Source:
PCinLife
The most interesting specification here is the shader compute power. Barts XT churns out 2.3 TFLOP/s with 1280 stream processors, GPU clocked at 900 MHz, while the Radeon HD 5870 manages 2.72 TFLOP/s with 1600 stream processors, 850 MHz. So indeed the redesigned SIMD core is working its magic. Z/Stencil performance also shot up more than 100% over the Radeon HD 5700 series. Both the HD 6770 and HD 6750 will be equipped with 5 GT/s memory chips, at least on the reference-design cards, which are technically capable of running at 1250 MHz (5 GHz effective), though are clocked at 1050 MHz (4.20 GHz effective) on HD 6770, and 1000 MHz (4 GHz effective) on HD 6750. Although these design changes will inevitably result in a larger die compared to Juniper, it could still be smaller than Cypress, and hence, more energy-efficient.
245 Comments on AMD Radeon HD 6700 Series ''Barts'' Specs Sheet Surfaces
It's about the family performance. The 6770 is the 4th most powerful performer after: 6970(?) > 6870 > 6850 > 6770
Whereas: 5970 > 5870 > 5850 > 5770
They are both fourth in the family. The relative power of it, i.e. 6770 = 5850 is utterly irrelevant.
I for one can't wanit to see what the spiritual successor to the legendary 5850 will be, BartsXT looks nice and all but CaymanPRO is what my sights are set on.
I fookin' hope they dont hump us all.
Nvidia and AMD have several teams working on different chips and generations of chips, so the fact that one chip is late doesn't affect others. It does shake the next releases a bit but mostly from a marketing standpoint, as they first want to sell some high-end chips, before they release the perf/price king (i.e GF100->GF104 == G80->G92). The original schedule in Nvidia was GF100 in Q4 2009, GF104 in Q1 2010 and mainstream/entry in Q2, rinse and repeat with next gen starting in Q4 2010. So basically GF100 was late by 6+ months, GF104 was late by 3 months and GF106 by 2 months or so. Next gen is not going to be late necessarily or too late, i.e Q1 2011 release. Remember that Nvidia doesn't need any re-design at the moment, they just need to add clusters or SIMDs to GF104 and have a "winner" in comparison to GF100 and that should be enough to compete with HD6000 cards.
For example, without engineers et all thinking too much (nothing at all actually :laugh:), adding one more cluster to GF104 you end up with a chip slightly smaller than GF100 (less than 3 billion transistors against the 3+ billion in GF100) but with significantly better specs:
Shaders: 480 SP -> 576 SP, 20% increase*
texture units: 64 TMU -> 96 TMU, 50% increase*
ROP: 48 same*
memory: 384 bit same*
* That's without taking into account that GF104 clocks much better than GF100, the new chip could be clocked at 800 Mhz easily and that would mean the new chip would be 30-40% faster than the GTX480, soundly beating the HD5970 and probably the HD6870 by the same ammount as the GTX480 beats the HD5870, except this time Cayman is said to be 400mm and NV chip would be a bit smaller than GF100.
On top of that and considering that finally TSMC's 40nm is at same yields as 55nm, Nvidia could decide to take the risk and instead of releasing a slightly smaller chip, they could go with a slightly bigger, but yummy yummy, chip. How? Same chip as mentioned above except they'd add one more SIMD to the SMs (note how small a cange this is and how easy to engineer/release it would be). GF104 is superscalar and its SMs have 3 SIMDS while having 2 schedulers, wasting one scheduler every odd clock cycle because it has no SIMD unit to talk to. The jump to 4 SIMDs at some point is unavoidable then, why not do it now, taking a small risk**? End result (and compared to GTX480):
764 SPs (+60%), 96 TMU (+50%), 48 ROPs, 384 bit. 750 Mhz...
** Small, because at this point 40nm yields are good, they know the process better and the resulted chip I estimate it would have 3.2 billion transistors and be smaller than GT200 in 65nm. That is, it wouldn't be the biggest chip Nvidia has made, but the benefits are enormous.
this next round of GPU wars is certianly going to be an entertaining one :D
That's why I think they will definatey not be in trouble. Unless you think they have been in real trouble in the past 2 quarters...
fudzilla.com/graphics/item/20315-radeon-hd-6700-detailed-on-slides
That being said, anything that drives down prices, I'm in favour of.