Quad SLI question

[ambam]

Is it really necessary to have four GPU's in an SLI or CFX setup?

Gaming benchmarks show only a very small increase in performance on a four-GPU setup. Some benchmarks do not show any fps increase at all.

Given the enormous power requirements of a quad GPU setup, is it really necessary to have such a system?

Also, four individual graphics cards in a PC uses up tons of physical space. It's wiser to use two dual-core graphics cards. Like the GTX 590 or HD 6990.

Personally, I'll take 3-way SLI GTX 580 (overclocked) over any other setup.

 

[phamhlam]

It is good if you are running a 5 monitor setup. The 4th GPU is almost always a bragging right or the thought of running everything in max with FPS never below 60.

 

[wojci028]

As far as I can tell there's no practical reason for running quad sli, but with the 580 especially there is really excellent scaling. This guy scales 4 asus gtx580s with over 90% efficiency! It might vary depending on your mobo/cpu I guess, but if you're willing to drop enough for 4 580s then you might as well get the best of the best for your mobo.

 

[monsta]

It isn't really necessary but it's an option for those who already have cards like the 6990 or 590 and want an upgrade from them to get more performance or life out of their system.

 

[Rizlla]

It has been shown in multiple benchmarks that going over a 2 way setup it does not justify the cost for the performance boost you get. 2 way is the best option. I would say either GTX590/GTX580/GTX570 SLi or HD6990/HD6970 CFX. Any of these setups will max out all current games.

 

[ambam]

It has been shown in multiple benchmarks that going over a 2 way setup it does not justify the cost for the performance boost you get. 2 way is the best option. I would say either GTX590/GTX580/GTX570 SLi or HD6990/HD6970 CFX. Any of these setups will max out all current games.

In percentages, how much performance do you get with having three cards instead of two?

I've got two HD 5870's and I can pretty much max any game with playable framerates, including Crysis without any anti-aliasing.

 

[dork_police]

the third card always drops the scaling a little, for instance if it goes

1 - 100%
2 - 198%
3 - 275%
4 - 348%

I just guessed the percentages but im pretty sure that they arent that far off, but AMD/ATI has been scaling way better than nvidia the last couple of series...

If I'd have enough money to buy 4x6970/2x6990 I'd go for the 4x6970 setup, as a 6990 can't keep up with 2 6970's... so there are bonuses to 4x 6970's/580's compared to 2x 6990's/590's because their performance is more limited than one of their single GPU counterparts....

 

[ambam]

the third card always drops the scaling a little, for instance if it goes

1 - 100%
2 - 198%
3 - 275%
4 - 348%

I just guessed the percentages but im pretty sure that they arent that far off, but AMD/ATI has been scaling way better than nvidia the last couple of series...

If I'd have enough money to buy 4x6970/2x6990 I'd go for the 4x6970 setup, as a 6990 can't keep up with 2 6970's... so there are bonuses to 4x 6970's/580's compared to 2x 6990's/590's because their performance is more limited than one of their single GPU counterparts....

The HD 6990 and GTX 590 are downclocked for heat and power consumption reasons. This is why two dual-core cards can't keep up with four individual cards.