SLI and sandy bridge (2500k)

[sofakingwetatdid]

I am trying to make a decision about Processor and Mobo, but my ignorance is getting the better of me. I had my mind all made up on a 2500k, but I know I will want to do SLI in the future. To be honest I am really confused by the pcie slots and functionality on 1155 boards. Every board I have seen seems to be limited to one pcie 2.0 x16. Some boards have additional pcie slots but seem to be limited to 2 8x lanes. Am I just missing something here? Is there no sandy bridge mobo for the person who wants to slap two big ole graphics cards inside?

 

[Why_Me]

I am trying to make a decision about Processor and Mobo, but my ignorance is getting the better of me. I had my mind all made up on a 2500k, but I know I will want to do SLI in the future. To be honest I am really confused by the pcie slots and functionality on 1155 boards. Every board I have seen seems to be limited to one pcie 2.0 x16. Some boards have additional pcie slots but seem to be limited to 2 8x lanes. Am I just missing something here? Is there no sandy bridge mobo for the person who wants to slap two big ole graphics cards inside?

There are a few 1155 mobo's that do 16x & 16x for dual graphics cards...Asus has two of those boards, Gigabyte has the UD7, and MSI has one I believe. As far as 8x & 8x are concerned...there's a difference of 3% while running dual cards vs a board that does 16x & 16x. Seeing how the 1155 SLI builds wipe the floor with any of the other builds...it's a no brainer imo.

 

[mortonww]

This 3% difference is quoted from an article on tom's in which the top two cards tested were the 4870X2 and the gtx 295. Is that right? I don't know that it still applies seeing as how we have single GPUs that are faster than both of those cards now. Who knows what the performance hit really is. I would imagine a gtx 570 SLI could show greater scaling with more lanes than a 4870X2 crossfire since one 570 is a significant bit faster than a 4870X2.

I just want to understand why I keep hearing this 3% number?

 

[Why_Me]

This 3% difference is quoted from an article on tom's in which the top two cards tested were the 4870X2 and the gtx 295. Is that right? I don't know that it still applies seeing as how we have single GPUs that are faster than both of those cards now. Who knows what the performance hit really is. I would imagine a gtx 570 SLI could show greater scaling with more lanes than a 4870X2 crossfire since one 570 is a significant bit faster than a 4870X2.

I just want to understand why I keep hearing this 3% number?

Agreed...the bigger/powerful the cards someone is running (dual cards) the more they would benefit from a 16x & 16x board. It's a shame imo that those boards cost so much. It's a rip off to the consumer.