So you're telling us that 16 lanes to two GPU's on one slot is somehow significantly different than 16 lanes to two GPU's on two slots?
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No eyefinity numbers yet :/
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Yup. Think latency... :yepp:
One single card, be it 1, 2 or a thousand GPUs share information than dump it on a 16x lane bus. Two GPUs over an (much slower) 8x pcie lanes have to share information back and forth over a much narrower band... It's a completely different thing.
Edit: My question is if this back and forth comunication over a "narrow" bandwidth, given the computing power provided by today's fastest GPUs driving a very high resolution proves to be a bottleneck or not.
you know that sli/crossfire connector thing.. its not only there for show.
the PLX chip isnt perfect either, and then there's that funny little feature that never saw the light of day since being mentioned for the 4870x2's...
I mean, if its that important why havent ATi been vocal about it?
I'm not sure if I'm following you right since English isn't my native language as you already probably noticed it... :)
All I'm saying is that no matter how much GPUs are in a single card, all of them is comunicating with the rest of the system as a whole with the given bus (pcie 1x, 8x or 16x).
I know there is not a magic interconnect chip speculated since before the 4870x2 launch. It's being speculated since before rv670x2 launch but I digress...
But saying a 2 Y GPU single card over a 16x pcie bus is the same as a 2 cards containing the same Y GPU over a 8x pcie bus is not correct (I know you didn't say this but the same principle applies). It doesn't matter if there's a CF/SLI bridge (wich have a finite bandwidth), they still have to comunicate with the rest of the system.
Pretty much what I had expected. Initially (as in last year ) I figured theyd have stuck with a Cayman Pro configuration to keep power draw and heat output at bay so I was a little shocked when the first mention of 375watts came to light but all said and done they positioned the product were it belongs. With that in mind why most would chose one over 2 6950s is beyond me. I'm sure the odd bencher will eat up a pair of these as I can see the attraction there but given the power envelope things have reached the benifts of such products are shrinking. Its not like you can throw one of these in a mATX case and expect it not to explode ;) ( and yes I know it can be nice to have 1 less PCIe slot occupied for those who use a lot of add in cards - this is one of the few things I enjoyed about the dual gpu cards I've used as I use tv tuners, sound cards and other devices )
I'm curious to see how these fair on water with a proper motherboard ( I wouldn't dare try to seriously overclock one of these on the average motherboard, melting 24pin connectors... no thanks )
Reviews
http://www.bit-tech.net/hardware/201...-6990-review/1
http://www.legitreviews.com/article/1566/1/
http://lab501.ro/placi-video/amd-radeon-hd-6990-review
http://techgage.com/article/amd_rade...s_card_review/
http://www.kitguru.net/components/gr...hd6990-review/
http://nl.hardware.info/reviews/2028...hd-6990-review
Wow, just finished reading most of those reviews. Cliff notes: expensive, incredibly loud, hot and you would be better served with two cooler running traditional single GPUs in X-Fire/SLI. Basically what I was expecting.
The price is too high, even a pair of 6970's is cheaper and performs better, I guess this is due to low stock and NVIDIA is yet to respond with the GTX 590.
the price will surely decrease, i think there's 2 reasons it's too high 1) they wait the 590 and so on will surely be able to kick it with a lower price, whatever is the perf of the Nvidia one. 2) availability ...
But after read some reviews, i really like the work have do AMD on it ... not completely perfect due to the 40nm... but well done.
5970 was pretty conservative on clock speed ( reference model ). The 6990 is all but not conservative. ( i want to believe this will maybe be a good lesson for next future high end cards )
Now AIB as Sapphire, Asus, Gigabyte, XFX have a nice support for work on it.. Im really curious to see what they can take out of this one.
( for peoples who want buy the card, it's urgent to wait and see what AIB's will bring )
We've just published our in depth tech article on the HD 6990 and we've also published a video review (swedish) on the card where we did some none scientific sound tests on tape. Our reference card has some pretty crazy coil whine which we dont know if consumer cards will suffer from but might be worth keeping in mind.
You can see the card in action here, Also hear it in action.
http://translate.google.com/translat...genomgang.html
Noisless room sound test at 15:15
ASUS GTX 580 DCII max load at 15:25
HD 6990 full load furmark at: 15:35
Notice the insane coil whine at 15:50
It remains to be seen if all cards have the same problems with coil whine during memory load. And it seems to be isolated to memory load and increase with memory frequencies.
Useless card ...