Tahiti's Bottleneck

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Borealis7

Platinum Member
Oct 19, 2006
2,901
205
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the same driver team that gave HD7XXX series 7-10% increase across the board with the 12.11 drivers?

forget it...i've been trolled :D
 
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parvadomus

Senior member
Dec 11, 2012
685
14
81
Ofc Tahiti bottleneck si the low ROP count. It should have been 48.
Hope next-gen 8970 be a 2560 shaders / 48 Rops monster, that will be amazing, up to 50% more performance over tahiti (best case), and 25%-40% average (over original 7970, if this reachs 1Ghz core.).
 

raghu78

Diamond Member
Aug 23, 2012
4,093
1,476
136
the bottleneck could be from the fact that Tahiti's front end needs more resources. GTX 680 has 4 GPC with 4 rasterizers and seems very well balanced. With 2 ACE, 2 tesselators and 2 rasterizers , Tahiti is not able to feed those shader cores. ROPs could be a bottleneck too. If AMD can double the front end resources , 4 ACE, 4 tesselators and 4 rasterizers , something of a dual pitcairn they should get better perf/shader.
 

SlowSpyder

Lifer
Jan 12, 2005
17,305
1,002
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I have always thought something internal wasn't keeping everything fed. If you look at a 5870 and a 5770, the 5870 is basically two 5770's on one die. Twice the SP's, twice the ROP's, twice the TMU's, twice the memory bandwidth, same clock speed. Yet two 5770's on CF were typically faster than a 5870, even with the CF inefficiencies factored in. You would think the 5870 would be the faster part as it has no CF 'tax' to deal with, yet it has basically twice the specs.

After the 2900 series AMD got rid of the ring bus and went to a hub, I wonder if that bottlenecks, if it cannot always feed SP's properly. Just a thought, because as your remove SP's the performance hit is often quite a bit less, percentage wise when compared with the percentage of SP's lost. That has been the case for a few generations now.
 

Red Hawk

Diamond Member
Jan 1, 2011
3,266
169
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no, My opinion of AMD's driver team has nothing to do with nVidia. Nice try buddy.

I like Amd cards a lot. I just think that the drivers lack polish more than I would like.

Well, what else is there to compare AMD's drivers to? S3?
 

Red Hawk

Diamond Member
Jan 1, 2011
3,266
169
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Maybe he wasn't making a comparison. You should try exploring more than one way of interpreting someone's argument.

Qualifying something as "shoddy" implies the existence of something that is "not shoddy".
 

lavaheadache

Diamond Member
Jan 28, 2005
6,893
14
81
I'm going to kindly step out of this thread because I think people's boredom is going to start some kind of stupid battle yet again.

FYI, read my friggin sig... obviously I have the hardware to back up my opinions, which that is all it is. An OPINION. I love my 7970's and wouldn't get rid of them for anything this generation.
 

3DVagabond

Lifer
Aug 10, 2009
11,951
204
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Maybe he wasn't making a comparison. You should try exploring more than one way of interpreting someone's argument.

Qualifying something as "shoddy" implies the existence of something that is "not shoddy".

Yes, I agree. It's all relevant, as the saying goes.

I think it depends on what you base it on. Lavaheadache, uses a lot of multi-gpu setups. This gen AMD appears to have some issues (I don't run crossfire. I'm going by reports mostly from [H]) with drivers in multi-gpu. Last gen there were no such issues. If we all remember the scaling for Cayman was pretty terrific. Towards the end there were individual game issues, but crossfire operated well, as a technology. Crossfire hasn't been as consistent for Tahiti, IMO.