SLI not working

[molinaf]

I am having trouble setting my sli connection. System specs are : Asus Formula VII 

                                                                                                       CPU: i7 4790k

                                                                                                        Memory: 8gb Corsair Dominator 

                                                                                                       GPUs: EVGA GTX 970 SC

                                                                                                                  MSI GTX 970 OC

                                                                                                          PSU: RM 850

I have tried different pcie slots, three different sli bridges, reset the drivers and BIOS. Any help will be awesome.

[ToniBamboni]

What problem are you having?

[molinaf]

SLI bridge isnt detected but cards work independently 

[Cerberus3]

Did you go into nvidia control panel and toggle sli mode on?

[molinaf]

Yes. I have but no good. I have heard of issues where different brands are the source of the problem. 

[Cerberus3]

AFAIK, all that matters is same model and vram, clock speeds may matter but I heard that the faster card just downclocks to the same speed as the slower card. I never heard brand was an issue.

[molinaf]

Ok. It sucks since it can't read the SLI bridge and I have three. Can it be any other hardware issues?

[Thx And Bye]

There shouldn't be any issues with different vendors. Only the modell matters.

All the rest is irrelevant (VRAM, clock speeds) If one card has more VRAM it can only use as much as the card with the lower one.

e.g. 4GB and 2GB VRAM in SLI equals to a total of 2GB usable VRAM.

The cards can (and should) run on different clock speeds, to avoid mico stuttering.

You can try using the other card as master (connecting the monitors to it). Also make sure all monitors are only connected to one card.

Also you can try using the other connector for SLI on the card. (it doesn't matter if you use the right or left ones).

Make sure, your board is SLI compatible and the cards are running at at least PCIe 8x.