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wonder squirrel
12-05-04, 07:32 PM
Hey folks, after some thinking on the subject, I got a question for you guys and gals.
First off I must say, the whole SLI thing is pretty sweet, only downfall (for me) is ofcoarse, expense. Not to piss on anyones parade here, but I was thinking, instead of using two video cards, why not go the dual core route instead? Seems thats the hot ticket for processors in the coming years, why not the GPU aswell?

I know there would be problems laying it out, but I (what would "I" know anyways) would think if they expanded the boards size abit, added a couple 3 or 4 molex connectors, they would be well on there way right? You may think 4 molex's is exetreme, but as it sits, 2 6800's require 2 each.
Plus 2 of the video cards together are pretty damn big. So if size isn't really an issue for cooling..What you do, get one large cooler (think in terms of a NV5 with taller profile fins) that exhausts air using a fan, a cooler that uses 2 PCI slots, using a 80mm fan laid down at a 45 degree angle, blowing over a simple, effective heatsink.
Put all the RAM on the backside of the card, using its own cooler, something low profile that could use the flow of air from the rear exhaust fan.


Now think about it. Put 2 GPU's on a single card, paired with 512Mb of RAM (a gig for you REAL sicko's), 2 DVI and 1 VGA out.

So, any thoughts?

GlowStick
12-05-04, 07:37 PM
Its a good Idea, but in pratice it dosent work out so well.

3DFX gave it a good shot, however then went out of business.

ATi gave it a shot and failed bigtime, in most cases only one vpu was being used.

XGi also gave it a shot and preformace is lacking on so many levels.

The advantage of haveing SLi, is you dont have to make a seprate product, if people want to run sli they buy two, if they only want one card, they buy one card simple as that, less to manufacture.

wonder squirrel
12-05-04, 08:08 PM
Its a good Idea, but in pratice it dosent work out so well.

3DFX gave it a good shot, however then went out of business.

ATi gave it a shot and failed bigtime, in most cases only one vpu was being used.

XGi also gave it a shot and preformace is lacking on so many levels.

The advantage of haveing SLi, is you dont have to make a seprate product, if people want to run sli they buy two, if they only want one card, they buy one card simple as that, less to manufacture.

I'm pickin up what your putting down here, but in the end, your still looking at a new motherboard(the board ads to manufacturer costs, albeit a different company), plus two cards. Not that big of a deal really, because chances are, you will be replacing the board for a PCI-e anyways.
I just thought a dual core (properly working-) would be a much better product (although more ram + new board + second core = price of two cards anyways)

Got any links to those dual core cards I could check out, or a model name/ number to look at? I'd be curious to just hear what they had on there plate.

-=DVS=-
12-05-04, 08:18 PM
3dfx Voodoo 5500 (to little to late), 6000 (never saw day of light 4 gpus)
Ati MAXX ( two gpus wasn't that fast at all )
XGI top models have dual gpus (can't compete with single gpus from ATi & Nvidia heck low end models are faster :lol: ).

Salamandar
12-05-04, 08:48 PM
Companies who made dual VPU/GPU didn't have a strong chip.
If you were referring to a dual core 6x00 GPU then forget it, you'll need more than water to cool that and it will make the card as big as the titanic!!
One more thing Dual GPU will make the card design rather complicated and also is not as future proof as the SLI.

(cheers)

wonder squirrel
12-05-04, 08:54 PM
I read the ATI Maxx review. From the get go, that sounded bad. I suppose years ago it might have been good, but the specs alone aren't very impressive.

I know there would be a cooling issue with the card, but I think it could be do-able with air and a well built heatsink. As it is, the nvidia cards in general are big, and really, even with a big ass heatsink setup, it would still require less space than the two cards plus two heatsinks

MUYA
12-05-04, 08:58 PM
Multi-GPU and multi-core is slightly different ;)

But with the Maxx debuted it was new tech then and manufactured on a large manufacturing tech 250nm? Perhaps when they slapped two cores together but they didn't have the knowhow then to get the two cores to talk to each other to share the workload as efficiently as possible.

These days the understanding of how to get 2 cores in one die to work properly should have come thru leaps and bounds. 90nm will allow more flexibilty to overcome transitor budgets possibly and maturity of the process should allow better yeilds

I also do not think Intel or AMD would pursue dual core bindly. Again not apples to apples as both are different ASICs but u get the jist? ;)

Filibuster
12-05-04, 09:10 PM
3dfx didn't go out of business because of SLI. Tons of people bought 2 Voodoo2 cards to run together - at $300 per card.
(They didn't have any real competition when they were doing SLI either.)

AGP killed SLI because of the single AGP slot. Even though multiple AGP interfaces are in the spec, nobody made a board to do it, probably because the AGP interface wasn't the bottleneck and the graphics chips were advancing so fast there was no point in putting two of them together. Just look at what happened a few months after the Maxx card came out. :)

3Dfx management just freaked out once they were threatened and screwed up beyond the point of no return.

The thing that killed the ATI Maxx was Windows 2000. Ati couldn't get the Maxx to work with both chips in Windows 2000 (poissibly due to the old driver team - has changed a lot now thankfully).

I agree with Salamander though, I don't think dual GPU cards (at high performance) are going to go because of the power and heat issues...its bad enough with one gpu.

GlowStick
12-05-04, 10:48 PM
Multi-GPU and multi-core is slightly different ;)

But with the Maxx debuted it was new tech then and manufactured on a large manufacturing tech 250nm? Perhaps when they slapped two cores together but they didn't have the knowhow then to get the two cores to talk to each other to share the workload as efficiently as possible.

These days the understanding of how to get 2 cores in one die to work properly should have come thru leaps and bounds. 90nm will allow more flexibilty to overcome transitor budgets possibly and maturity of the process should allow better yeilds

I also do not think Intel or AMD would pursue dual core bindly. Again not apples to apples as both are different ASICs but u get the jist? ;)
Ah your right, why have two cores when you can make one core that dose the same work as two but in a cheeper one chip solution?

BladeRunner
12-06-04, 02:48 AM
The Anandtech article I was linked to recently by a member here sums it up nicely:

By now you can begin to see where the performance benefits of SLI come into play. With twice the GPU rendering power you effectively have a 32-pipe 6800GT with twice as much memory bandwidth if you pair two of the cards together, a configuration that you won’t see in a single card for quite some time. At the same time you should see that SLI does have a little bit of overhead associated with it, and at lower CPU-bound resolutions you can expect SLI to be slightly slower than a single card. Then again, you don’t buy an SLI setup to run at lower resolutions.


and a sum up:-

We’ve already seen that going from a single $200 GeForce 6600GT to a pair of them offers performance greater than that of a single $400 GeForce 6800GT. Take into account that the price of these cards goes down over time and you’re looking at a pretty decent upgrade path for the future, requiring minimal investment today.

The upgrade path for 6800GT owners is even more enticing; if you’ve only got $400 to spend on a card today you can’t beat the 6800GT as a single card solution. Then, as the price of the 6800GT drops, it may become more attractive for you to upgrade to a second card rather than buying a next generation GPU. As long as we’re between DirectX cycles, SLI enables you to have the fastest most robust graphics setup out there without missing out on much.


Full article HERE (http://www.anandtech.com/video/showdoc.aspx?i=2284&p=1)

So now all I want to know is how long untill we can get a mobo with 4 PCI-E vga cards slots, and dual cpu's (xmasgrin)

Filibuster
12-06-04, 07:25 AM
With a dual core/gpu card there wouldn't be worries about duplicated memory use between the two cores since they would share a common memory pool anyway. The only problem would be making sure there is enough bandwidth on one card to feed both cores :beer2:

A 512bit memory crossbar would double the memory bandwidth but pincount would be sky high.

Salamandar
12-06-04, 08:23 AM
With a dual core/gpu card there wouldn't be worries about duplicated memory use between the two cores since they would share a common memory pool anyway. The only problem would be making sure there is enough bandwidth on one card to feed both cores :beer2:

A 512bit memory crossbar would double the memory bandwidth but pincount would be sky high.

I 2nd that!

wonder squirrel
12-06-04, 08:54 AM
It would deffinately be a large, complicated design, and a very crowded board, but it would pretty sweet assumiung you could get everything to play well together (that seems to be the biggest setback of the cards mentioned before)

Edge
12-06-04, 09:23 AM
All things considered, the dual-core design of the Voodoo 5500 actually worked out quite well. The problem is that the product was delayed for so long, faster single-chip cards came out, and the speed advantage the two chips had was nullified. But, compare the Voodoo 4 to the Voodoo 5: exact same design, but the Voodoo 5 used 2 (or 4 in the case of the 6000) cores while the Voodoo 4 used 1. Overall, it was pretty efficient, even if it did have a few shortcomings such as still spliting the ram between the two cores.

Unfortunatly, pulling off the same feat today would be a much tougher challenge. The cards are ALREADY unbelievably huge (I had to move my harddrives around in my computer just to fit my 6800 in!), and cooling issues are a big problem. The nice thing about dual-cards is that they can still operate independantly. You don't NEED to get 2 cards right away: if you buy a 6x00 card right now, you could at any point in the future buy another one and you'd instantly double your performance. Your current card doesn't go to waste, and it would be far cheaper. And on top of that, you even have the option of splitting up your two cards and putting them in different machines, or if one breaks you aren't totally screwed liked you would be with a single videocard. A single multi-GPU card would be a nice way to brag about having a video card that's faster than anything else out there, but for pure functionality an SLI solution is superior. The only problem is that you need a dual-PCI motherboard to take advantage of it...