Does this Motherboard Support 3 Way SLI?

jdenova007

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It only has 3 PCI-E slots in 8x 8x mode... if you add the 3rd PCI-e slot it gets shared with PCI-e 1 and brings PCI-E slot 3 down to 4x mode....

I think when they say "quad" they mean 2 cards each with 2 cards "inside" of them... some cards are considered 2 in one... so I'm guessing this is "quad" means to them; because it does NOT have 4 PCI-E slots...

Just my guess(I may be totally wrong).... I'm sure someone else will be able to clarify further.
 

jdenova007

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Actually see this - In early 2006, NVIDIA revealed its plans for Quad SLI. When the 7900GX2 was originally demonstrated, it was with two such cards in a SLI configuration. This is possible because each GX2 has two extra SLI connectors, separate from the bridges used to link the two GPUs in one unit – one on each PCB, two per GPU, for a total of two links per GPU. When two GX2 graphics cards are installed in a SLI motherboard, these SLI connectors are bridged using two separate SLI bridges. (In such a configuration, if the four PCBs were labeled A, B, C, D from top to bottom, A and C would be linked by an SLI bridge, as would B and D.) This way, four GPUs can contribute to performance. The 7950GX2, sold as an enthusiast-friendly card, omits the external SLI connector on one of its PCBs, meaning that only one SLI bridge is required to run two 7950GX2s in SLI.

Taken from here - http://en.wikipedia.org/wiki/Scalable_Link_Interface
 

ph0en1x26

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it says the 3 rd PCI is default x1, i assume by default it can be changed, IE to 4x when i card is inserted?
 

jdenova007

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even so... the 3rd slot will run at 1x.... not 4x.... he is showing you the 3rd slot by ITSELF... when you add in PCI-e 1 and 2, it shares their bandwidth and will probably take a big hit going down to 1x. Again, I am not positive.

He also says at the end "how PCI-E speed affects single card performance".... not SLI 18x 8x 1x...
 

COLGeek

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+1. This is the correct interpretation. Regardless, 3-way is possible and will yield some benefit over 2-way SLI.
 

ph0en1x26

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that one card he was running on the 4x slot had 2 GPUs in it... so they were both running at 2x2x like he says, Im not convinced itd run at 1x... just doesnt sound right
 

COLGeek

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It will run, but just not as "fast" as the other PCIe slots. Essentially, you will be saturating the bus. Really, you can expect more than 100% use of the bus and you will be right there.
 

Hit-teh-X

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Theres an option in the bios to change the last slot to 4x or 1x. In doing so you loose the eSata port and a few USB3.0 ports I believe.