I suggest that you read this thread before parting with your money. https://forums.macrumors.com/thread...nce-after-sending-unflashed-gtx-1080.2106434/
Ok.. But you see I already have both of them inside my Dell Precision T5500 PC.. However SLI is not supported in my Dell.... But it would be nice if I could use one in my Mac (They have 3 cooling fans)...
I suggest that you read this thread before parting with your money. https://forums.macrumors.com/thread...nce-after-sending-unflashed-gtx-1080.2106434/
Does SLI have any real possibilities in macOS with eGPU's on the horizon? Likely would not benefit much on a cMP 5,1 but would give some hope for future MacPro's.
You can use then on the Mac now, flash is not required unless you need the boot screen.
Also, I think SLI can be enabled by software method if the motherboard is not supported.