Llano IGP vs SNB IGP vs IVB IGP

Heh, Kaotik, your oversight reminds me of this gem from AMD's Bulldozer blog:

Blog text said:
Our design engineers estimate that this will drop the power consumption by up to 95% in idle over the previous generation of processor cores[...].
Meanwhile said:
95% drop in idle state over previous generation is quite impressive. --commenter

The 95% number is a comparison of a core in idle and a core in C6 state, this is not a comparison of 2 different generations. --blog author

I'm still trying to figure out if this is PEBKAC on my part.
 
Whoops, should have read more than the subject line :oops:
Though it sounds weird, that they'd call it E2 since E2 is Llano based CPU, too.
 
there's another "incongruence"
the comparison is only about visual performance, E350 ha 80 radeon cores, A4 has 240 but is only 143% faster that is about less that 200cores
 
there's another "incongruence"
the comparison is only about visual performance, E350 ha 80 radeon cores, A4 has 240 but is only 143% faster that is about less that 200cores
Quite the contrary the scaling is ok. 80->240 cores but the E350 has 12% higher gpu clock. Getting 2.43 the performance with only 2.7 times the shader power is quite good scaling. It also only has twice the rops (again, a bit less effectively due to clock), and memory bandwidth is also scaled according to the performance. There's also the cpu part of the benchmark to consider, which I'm too lazy to look up any numbers.

btw the gpu clocks are imho amazingly low. Consider mobility redwod (madison), which had 450-600Mhz clock for the HD 5650 mobility and up to 650Mhz for the other redwood based mobility 57xx parts.
This is why I was (wrongly) thinking Llano would have less simds than redwood initially, because 32nm SOI should enable at least slightly higher clocks, no? But instead we get lower clocks. I can only guess it's more power efficient than a cut-down gpu with higher clocks would have been, but the clocks are so low it's almost hard to believe.
 
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btw the gpu clocks are imho amazingly low. Consider mobility redwod (madison), which had 450-600Mhz clock for the HD 5650 mobility and up to 650Mhz for the other redwood based mobility 57xx parts.
This is why I was (wrongly) thinking Llano would have less simds than redwood initially, because 32nm SOI should enable at least slightly higher clocks, no? But instead we get lower clocks. I can only guess it's more power efficient than a cut-down gpu with higher clocks would have been, but the clocks are so low it's almost hard to believe.

These are numbers for the mobile parts, most of which will have Turbo enabled on the CPU and GPU.
As an example the C-60's GPU has a 280MHz base clock, but it turboes up to 400MHz.

That's a 43% overclock. Apply that same ~40% overclock to Llano GPUs and you get the ~550MHz clocks you were looking for.

But don't forget the TDP for mobile Llanos is 45W at most. HD5650M has a 20W TDP and quad-core Champlains have a 45W TDP. There's definitely a gain in power efficiency here.




Furthermore, it seems most Llano laptops will bundle discrete cards for Crossfire, so the largest game changer might turn out to be the price/performance ratio for budget systems.
 
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Quite the contrary the scaling is ok. 80->240 cores but the E350 has 12% higher gpu clock. Getting 2.43 the performance with only 2.7 times the shader power is quite good scaling. It also only has twice the rops (again, a bit less effectively due to clock), and memory bandwidth is also scaled according to the performance. There's also the cpu part of the benchmark to consider, which I'm too lazy to look up any numbers.

This is Vantage you are talking about here, and I dare say that looking at that to judge scaling for these ICs is dubious either way. I can't imagine that they will ever be able to produce decent playability with that kind of graphics code. To get reasonable playability with these parts, you will have to adjust settings to something sympathetic. Which, in a sense, is OK. Judging them on the basis of extremely heavy benchmarks constructed to justify sales of new hardware isn't meaningful. Can they do a decent job of WoW? Diablo 3?

These aren't e-penis parts, and shouldn't be measured using e-penis measurement tools.
 
These are numbers for the mobile parts, most of which will have Turbo enabled on the CPU and GPU.
As an example the C-60's GPU has a 280MHz base clock, but it turboes up to 400MHz.

That's a 43% overclock. Apply that same ~40% overclock to Llano GPUs and you get the ~550MHz clocks you were looking for.
Yes that's true. I haven't seen any turbo numbers for the GPU part anywhere, so if they can indeed turbo up 40% it makes more sense.

But don't forget the TDP for mobile Llanos is 45W at most. HD5650M has a 20W TDP and quad-core Champlains have a 45W TDP. There's definitely a gain in power efficiency here.
It just seemed like they sacrificed quite a lot of frequency for not much more power efficiency. Buy if it can clock to 550Mhz with still active cpu I guess it's ok.

Furthermore, it seems most Llano laptops will bundle discrete cards for Crossfire, so the largest game changer might turn out to be the price/performance ratio for budget systems.
If that really is a regular HD6750M that notebook is shipping with I don't think it would be terribly useful for CF (quite asymmetric already).

This is Vantage you are talking about here, and I dare say that looking at that to judge scaling for these ICs is dubious either way. I can't imagine that they will ever be able to produce decent playability with that kind of graphics code. To get reasonable playability with these parts, you will have to adjust settings to something sympathetic. Which, in a sense, is OK. Judging them on the basis of extremely heavy benchmarks constructed to justify sales of new hardware isn't meaningful. Can they do a decent job of WoW? Diablo 3?

These aren't e-penis parts, and shouldn't be measured using e-penis measurement tools.
Oh, agreed - but they are the only numbers so...
That said, scaling could be similar in games, even with lower settings. The cpu is a lot faster than the E350, so is the GPU, and memory bandwidth too.
 
Cayman's Powertune limiter is essentially GPU Turbo, huh? It just spends most of its time at max clock because it's almost unrestricted in its power usage. Llano will be the second implementation of this then but with much more strict limits.
 
Cayman's Powertune limiter is essentially GPU Turbo, huh? It just spends most of its time at max clock because it's almost unrestricted in its power usage. Llano will be the second implementation of this then but with much more strict limits.
Cayman's Powertune isn't terribly efficient though since it can't (I believe) change voltage.
Though since Llano's gpu clock is a lot lower maybe it wouldn't matter there (the different clock states might have the same specified voltage, much closer to idle voltage than Cayman). Or it's improved to change gpu voltage too, much like the cpu.
Also I certainly would expect this to be coupled with cpu turbo, so I'm not sure it is really that similar to Powertune.
 
There's also the cpu part of the benchmark to consider, which I'm too lazy to look up any numbers.

3DMark Vantage Formula

http://www.extremetech.com/article2/0,2845,2289656,00.asp

3DMark Vantage on Brazos

http://www.tomshardware.com/reviews/amd-fusion-brazos-performance,2790-3.html

548 GPU
2038 CPU

=670 3DMark Vantage score(Interesting, so they took Tomshardware results for comparison)

Phenom II-based Turion II Neo K625 gets 2459 in 3DMark Vantage CPU at 1.5GHz frequency.

Score=1625
CPU=2459
GPU=??
Using formula = 1460 = 2.66x


Assuming linear scaling to 1.9GHz

Score=1625
CPU=3115
GPU=1402 = 2.56x
 

SNB looked more like 1/5 to me.
Also, that figure obviously counts L3 as non-GPU - you could just as well argue it belongs to the GPU in which case the gpu would be bigger than all cpu cores :).
Really though I think if you want to look at cpu/gpu balance you should look at the parts which are exclusive to these parts - so don't count L3, MC/NB. In this case the GPU part looks like about 60% of the cores which isn't too shabby actually (that's just a gross estimate from a quad core SNB).
Also, I'm not too sure that 1/3 part there on IVB really is gpu anyway.
 
The architecture really needs to have a sufficient L3/core ratio. Each core needs a tile of L3 if it's to be wortwhile.
The GPU uses the L3 as well, though I have not seen an analysis of how much.

It is interesting that Intel is maintaining the very rectangular die shapes for these smaller dies. Perhaps it is the ever-expanding IO capability or some quirk of the Intel's modular design.
 
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