AMD: Southern Islands (7*** series) Speculation/ Rumour Thread

Clearly CU organize in groups of 4,not tie to setup engine.

I guess both Pircorn and Cape Verde will be single setup engine,Pitorn 20CU and Cape Verde 12CU.

 

Why discuss about such a low-res image?

 

nice
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You got that the wrong way around. 1 GB is officially 10^9 Bytes, not 2^30 Bytes. The latter number has the official IEC designaton of 1 GiB, AnarchX is completely correct. Just ask the harddrive manufactures about the units they use.
PS:
The JEDEC still uses the binary definition with GB, but it is not consistent.

 

Whoa! I didn't even realized that the drivers allow bezel compensated mixed size monitors until I noticed the driver version on one of the slides. Thanks ATI/AMD/Dave/+Driver team.

 

That may be recently true but i'v been taught years ago that 1 GigaByte = 1024 Mega Bytes, 1MB = 1024kilo bytes, 1 Kilo Byte = 1024 Bytes, 1 Byte = 8bits.

Now just because some standards institution decided to change that due to consumer vs hard drive industry marketing confusion doesn't make it in my view a correct decision. Only made it worse and prone to more confusion and mis-comunication/interpretation.

 

Actually they didn't change anything, you (like most) were just taught wrong because some HDD manufacturers etc decided it's better for marketing.
"Giga" means 1 000 000 000, not 1 073 741 824

 

That depends on which standardization institute you follow. In traditional Computer Science Kilo/Mega/Giga is a power of two (since that was closest to the decimal system) but as far as I see it, IEC invented the irritatingbytes just because they think that whatever is commonly used isn't good enough, it needs to be exquisite..

IF the IEC suddenly wants to rename the byte to "handful of applesauce" I also don't think that any sane person will start using that.

On-topic: on the PCB print above, you can see both types of fans traced out on it.

 

meanwhile everyone knows that for memory sizes it's always been about multiples of 1024 and will stay that way.

 

I know you are not supposed to read too much in to these marketing slides, but it seems to me that AMD has tied ROPs/TMUs/CUs to screen space tiles.

 

And that same slide shows the ROP partitions kept the colour/depth caches, despite the introduction of coherent L2 for global sync.

 

Because it looks better.
If you look at the Cayman slides, you'll see RBE - L2 Cache (128 KB) - RBE, RBE - L2... (4 times):
8 RBEs and 4x128 KB L2 cache.
But now it looks like there are 6x128 L2 Cache. 8 RBEs and 6x128 KB L2 Cache - not good.

Question: every CU group (4 CU) has now its own Instruction/Constant Cache)?

 

Yep.

 

Man, I would be in heaven if it allowed the use of PLP setups. I'm thinking it probably won't but I've got my fingers crossed that if not now then hopefully it's a step in that direction.

Actually Giga"byte" was always multiples of 1024 (or powers of 2) long long before HD manufacturer's entered the picture.

That standards body erroneously attributed GB to the HDD standard rather than the computing standard (byte -> Kilobyte -> Megabyte -> Gigabyte) which predates it by quite a few years. Hence all the confusion among people.

Going by their incorrect standards, you'd have to modify all past texts to KiB, MiB, etc. to match the ridiculous GiB.

Thanks but I'll be sticking to the old and more correct version of GB.

Regards,
SB

 

I believe it was just about maintaining consistency across scientific fields: 1 kW is 1000 W, 1 km is 1000 m, 1 kg is 1000 g, etc., so they wanted 1 kB to be 1000 B. A seemingly reasonable idea, that turns out to be horribly inconvenient in practice. I don't think I've ever used kiB/MiB/GiB, or that I ever will.

 

Actually, ROPs where always tight to (a certain interleaved set of) screen space tiles. It makes the Color- and Z-caches more efficient. And with Cayman (Cypress and Barts too) the raster units were also asssigned interleaved screen space tiles. But I doubt the same is done with the CUs in GCN.

 

It might not be such a bad idea. The cache sizes for ROPs are small and regularly hitting the crossbar for syncing would be bad for power.

 

But CU groups needs to tied to setup engine too...

I think it's better for essential-class to have only one setup engine too.

 

so wheres the leaked benches?

 

Not even card pics have been circulated widely (ie by multiple sources) so far. God knows when benches would come.

It might be a sign of low initial availability.