Mosaic setup

Rank newby here and have trawled the search engines with no luck.
Three HP workstations with Quadro M5000, M4000, M2000
Running through an Aten DP1.2 KVM
Dual Dell U2717D monitors in daisy chain configuration DP/mDP
For the two monitors to act as a single wide display - presumably a Mosaic
The two are acting as clones both showing the same stuff although in NVIDIA Control Panel Cloning is shown as disabled. Control Panel shows each card as Single GPU Sync but the Create New Configuration link is not active.

Info on how to spread the desktop across the two would be most appreciated.


Should have added OS Win-10 64-bit

The Solution
In the monitor menus set MST (or DP1.2) ON for the first monitor in the chain and OFF for the second.
Then NVIDIA Control Panel/Mosaic will show the GPU and two monitors. Click Create New Configuration and follow the steps (check cabling as correct). Don’t worry when the monitors blink on and off a few times while mosaicing is being set.