Motherboard SLI Compatibility? (GA-Z77X-UP5)

[mercier001]

Hello,

The Gigabyte webpage for my current mobo says it's SLI compatible (http://www.gigabyte.com/products/product-page.aspx?pid=4279#sp) but the board isn't listed in the SLI compatible list on Nvidia's website (http://www.geforce.com/hardware/technology/sli/motherboards?field_manufacturer_value=GIGABYTE&field_socket_type_value=LGA+1155&field_sli_support_value=All) and I do not find results on Google regarding SLI with this board.

I intend to put 3 graphics card on this motherboard with two of those (having the same GPU) running in SLI. This rig is for GPU rendering purposes (Octane et al).
But now I'm thinking maybe I need a new motherboard, so how do I make sure my motherboard is compatible with SLI and if it is 2,3 or 4 way compatible?

Thanks in advance

 

[spooky2th]

Yes, it will support 3 cards in SLI. Here is a cut & paste from the Gigabyte web site.

1 x PCI Express x16 slot, running at x16 (PCIEX16)
* For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.

1 x PCI Express x16 slot, running at x8 (PCIEX8)
* The PCIEX8 slot shares bandwidth with the PCIEX16 slot. When the PCIEX8 slot is populated, the PCIEX16 slot will operate at up to x8 mode.

1 x PCI Express x16 slot, running at x4 (PCIEX4)
* The PCIEX4 slot is available only when an Intel 22nm (Ivy Bridge) CPU is installed.
* The PCIEX4 slot shares bandwidth with the PCIEX8 and PCIEX16 slots. When the PCIEX4 slot is populated, the PCIEX16 slot will operate at up to x8 mode and the PCIEX8 will operate at up to x4 mode.
(The PCIEX16, PCIEX8, and PCIEX4 slots conform to PCI Express 3.0 standard.)
* Whether PCI Express 3.0 is supported depends on CPU and graphics card compatibility.

 

[mercier001]

Thanks spooky2th, though the part you copy pasted doesn't mention SLI.
Should I conclude that, as long as the motherboard is SLI compatible, SLI will function correctly for as many x16 slots are available on the board?
Or that there is no such thing as an SLI compatible mobo with four x16 slots but only capable of 3-way SLI, for example?

 

[spooky2th]

It says that a single device (GPU) in the fist slot, the slot will run at x16 bandwidth. If a second, is installed in the next slot (the x8 slot) they both will run at x8. If a 3rd is installed in x4 slot, (When the PCIEX4 slot is populated, the PCIEX16 slot will operate at up to x8 mode and the PCIEX8 will operate at up to x4 mode.)

There is only a total of x16 bandwidth that they all share. GPU's cannot even get close to the x16 bandwidth to begin with. The same with 3 high end GPU's, not even close.

Z79, Z99 and the new LGA1151 boards offer more lanes. Here's an example of a Z99 board with 4 GTX 980's.

http://www.pcper.com/reviews/Graphics-Cards/NVIDIA-GTX-980-3-Way-and-4-Way-SLI-Performance

 

[mercier001]

Oh OK I understand now. Thanks a lot!