Z77 3 way sli

[electrolaser]

well, we know that the z77 chipset has only 40 pcie lanes which limit most new boards to something like 8x/8x 2x pcie 3 ( technicaly x4 2.0) which would seem to proclude triple sli in any form however
I was looking at this and this
http://www.techpowerup.com/reviews/Intel/Ivy_Bridge_PCI-Express_Scaling/10.html
http://www.hardocp.com/article/2010/08/25/gtx_480_sli_pcie_bandwidth_perf_x16x16_vs_x4x4
http://www.tomshardware.com/reviews/pcie-geforce-gtx-480-x16-x8-x4,2696-17.html
and barring thermal and space requirements and the fact that it might take speed from peripherals it actually might be feasible
(I don't really intend on doing this I heven't the psu/cash, just curious)
I mean even at x1 pcie 3 equivalant some games run pretty nicely, considering
and that's with a single card, your review said that both sli and higher resolutions lessen the impact a lot
which makes sense seeing as most of memory is synced over the bridge.
so has any one tried this?

 

[jaquith]

No 'we' don't know the LGA 1155 Z77 has (40) PCIe lanes, but the LGA 2011 platform does offer 40 PCIe lanes. All LGA 1155 are limited to 24 PCIe lanes -- typically as 16 lanes for the GPU as either PCIe 2.0 or PCIe 3.0 and 8 lanes of PCIe 2.0 for the chipsets.

To acheive 3/4-WAY SLI/CF Z77's the MOBO must use a 'PLX' chipset to 'create' additional lanes that are 'funneled' back to the CPU's 16 lanes.

The data you are looking at isn't the typical configuration for 3 or 4 WAY SLI/CF, instead most all are running 3xHD monitors or 5760x1080 (more with bezel correction). Next as you increase the Details and especially items like 8xAA then you begin to saturate. It becomes apparent with 4-WAY SLI; see - http://www.evga.com/forums/tm.aspx?m=1537816 PCIe 2.0 vs PCIe 3.0 in x8/x8/x8/x8.

 

[blazorthon]

^+1

PLX motherboards are mostly expensive. I don't think that there any Z77 boards with a PLX chip are under $200 (at least not any using PCIe 3.0, there might be some that are cheaper with PCIe 2.0). It would probably be no cheaper than an LGA 2011 build with an i7-3820 and a decent $200 to $280 motherboard.

 

[electrolaser]

oooops; sorry noob mistake.
k, thanks for the answer anyway, shame though

 

[patrickcrowely]

This is a good post, been researching this for awhile & didn't know they went back this far. Thanks