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Message 43412 - Posted: 2 Nov 2010, 8:36:56 UTC

Like nVidia does?
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Message 43415 - Posted: 2 Nov 2010, 12:40:47 UTC - in response to Message 43412.  

Yes, but to a far lesser degree, thats why DP performance in projects like MW is far better than NVidia cards. The cards themselves are more powerful $ for $ anyway, but add in the mix the cripple rate for DP, and its clear why ATI flys more at DP than NVidia.

However the game changes with the 6XXX series cards. 68XX is not DP enabled, its aimed fair and square at the mid range gamer market (5770 territory), where people could care less at DP performance, and care more about cost and bang for the buck.

ATIs (AMD) future DP enabled card is the 69XX series, Cayman, first of which is due on the shelves first week December. Whilst reality has yet to be physically seen, its confidently expected the 69XX series will have DP. Its not clear yet to what level they cripple it to retain clear water with the Industrial Cards. What is clear already is that it will be a marked improvement on the 5970.

At that point its game set and match for AMD as they will have two high end cards (5970 & 69XX) way out performing NVidia 4XX. NVidia are on the point of a paper launch of the 580, but you will not see that on the shelves until next year, it is in any case what the 480 should have been initially. Be wary of impending NVidia spin re the 580 on a significant scale.

Interesting times, far more so than the usual "leapfrogging" of card capability from the Red and Blue teams. This is a life changer, and will leave NVidia for dead, not that they are competing at present anyway. Lets see the physical reality mid December/early January, but on AMD/ATI past record, and NVidia's record of spin, its going to be close to the physical outcome.

If you are mulling over a buy, I'd wait a few weeks, this change in card series is going to have a big impact, and it would be wise to await the physical reality mid-end December.

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Zy
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Message 43433 - Posted: 2 Nov 2010, 21:15:15 UTC

AMD puts a software limit on currently supported DP cards?
Cards like the 5770 simply don't have the feature.

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Message 43434 - Posted: 2 Nov 2010, 21:24:44 UTC - in response to Message 43415.  
Last modified: 2 Nov 2010, 21:26:35 UTC

Yes, but to a far lesser degree, thats why DP performance in projects like MW is far better than NVidia cards.....


The 5770 does not have the FP64s on board by design, as it is aimed at the mid range gaming market, so there is no question of DP, it cant physically do it.

The 58XX cards have DP, and like NVidia AMD do limit the DP ability to avoid consumer cards outperforming Industrial Cards, but to a far lesser degree than NVidia. AMD DP performance is therefore better than NVidia in 58XX.

The 68XX cards replace the 5770, and will also not have DP.

The 69XX cards replace the 58XX & 5970 cards and will have DP - its assumed the DP crippling will be at the same rate as 58XX, but lets see reality in December.

Regards
Zy
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Message 43435 - Posted: 2 Nov 2010, 21:45:57 UTC

Nvidia DP = 1/8 SP
AMD 1/5
Thus a 5870 @ 2720 = 544 DP which is almost as good as the Tesla C2050!!
Without ECC capability tho.
Way more bang for your buck!
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Message 43436 - Posted: 2 Nov 2010, 22:29:08 UTC

I'm looking at the DP performance between the FireStream and Radeon line and they both have the same 1/5 SP performance. Why would the FireStream GPU have the same "limitation"?
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Message 43585 - Posted: 8 Nov 2010, 8:37:14 UTC
Last modified: 8 Nov 2010, 8:43:24 UTC

I readed on net that DP not have in 68xx but it is on unclear for 69xx.
One user form folding forum, moderator told that FP64 is dropped from 6K series cards. It is unclear to me it is for 68xx or affect for 69xx too. He not talk what cards dropped suppot and he told that CAL BROOK+ is history too. 6K for only OpenCL.
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Message 43586 - Posted: 8 Nov 2010, 8:44:09 UTC - in response to Message 43585.  

I readed on net that DP not have in 68xx but it is on unclear for 69xx.
One user form folding forum moderator told that FP64 is dropped from 6K series cards. It is unclear to me it is for 68xx or affect for 69xx too. He not talk what cards dropped suppot and he told that CAL BROOK+ is history too. 6K for only OpenCL.


From SemiAccurate.

"There are a lot of really bad rumors going around the net right now so be careful what you believe. The two things that we know are true is the memory speed and that barring a last second glitch, you will be buying them before Dec 1. Everything else should be taken with a glacier sized grain of salt."
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Message 43587 - Posted: 8 Nov 2010, 8:52:15 UTC
Last modified: 8 Nov 2010, 8:55:06 UTC

I not belive nothing, i just wait here.
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Message 43648 - Posted: 9 Nov 2010, 23:32:39 UTC - in response to Message 43436.  

I'm looking at the DP performance between the FireStream and Radeon line and they both have the same 1/5 SP performance. Why would the FireStream GPU have the same "limitation"?


Because unlike nVidia ATI doesn't cripple DP performance on consumer cards to prop up the premiums on their workstation cards (although if they decide to compete against Tesla in the super computer market I would be surprised if they don't change their tune).

What they don't do, and what nVidia hasn't done outside of the GF100 chip (and presumably the GF110), is to support DP in hardware to the maximum amount possible (SP/2). The reason ATI doesn't do it, and nVidia hasn't done it on their other chips is that the 99% of their customers who don't take advantage of GPGPU never use it which means that the die area that is being taken up to support FP64 (and some *is* needed for setup/teardown activities and linking 2 32 bit pipes into one 64bit pipe even though most of the FPU is shared) instead of being used to place more shaders/texture units/rops/cache/etc that the 99% of people who buy them for gaming performance only care about. Alternatively they could make the dies slightly smaller and cheaper for a higher profit margin, or sell the cards for less to gain market share.


That said however, nVidia is nerfing FP64 more than is strictly needed to protect their Tesla cards. The C2050 (Tesla equivalent of a GTX480 with 3GB ram) is priced at $2150 by the only company I could find selling it. With 480's running $450-500, FP32/6 wouldn't seriously threaten the Tesla market. After factoring in the power consumption, cooling costs, and rack space even FP32/4 would probably be safe. However until a mass marketish consumer need for GPGPU-FP64 support emerges I wouldn't hold my breath on them loosening up much.
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Message 43735 - Posted: 11 Nov 2010, 10:42:42 UTC
Last modified: 11 Nov 2010, 10:47:05 UTC

Looks like I'm buying the HD 6970 then.

nVidia: software limitation (cripples hardware) 1/8 FP32
AMD: hardware limitation (though not crippled) 1/5 FP32
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Message 43745 - Posted: 11 Nov 2010, 17:00:11 UTC - in response to Message 43735.  
Last modified: 11 Nov 2010, 17:05:21 UTC

Looks like I'm buying the HD 6970 then.

nVidia: software limitation (cripples hardware) 1/8 FP32
AMD: hardware limitation (though not crippled) 1/5 FP32


You mean not FP32 and maybe think FP64. That FP64 is important.
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Message boards : Number crunching : Does AMD cripple DP performance?

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