2x 1080p + 1x 4k help

[tougas]

I finally got my hands on 2 gtx 980's and I want to venture into the 4k gaming community. I'm aware of the frame rates and the workload for a 4k monitor and I figured running 3 monitors, 2@1080p and 1@4k would be too strenuous while gaming then I think I came up with a solution. Would it be possible for me to put the gtx980's in sli dedicated to the 4k monitor and have a 3rd GPU, say my old gtx 670, to run the tertiary 1080p displays? My Mobo can handle 3 GPUs I'm just curious if anyone has any input/suggestions. Thanks for the help

 

[tougas]

Or as another option, I have the Asus maximus VI formula Mobo which has a display port and an HDMI port, couldn't I use those to power the two displays? I only ask because I just checked and the Mobo only supports 1x16, 2x8, or 1x8 2x4 and I don't want to lower the gtx980 capabilities

 

[nick779]

Or as another option, I have the Asus maximus VI formula Mobo which has a display port and an HDMI port, couldn't I use those to power the two displays? I only ask because I just checked and the Mobo only supports 1x16, 2x8, or 1x8 2x4 and I don't want to lower the gtx980 capabilities

Your processor/motherboard doesnt support enough PCIe pipelines to not bottleneck 3 GPUs.

I however dont really know what the limitations with running different cards with totally different architectures, or if its even possible.