Hi Cley Miguel,
Are all three displays the same?
What Drivers did you have installed previously?
I would recommend using those drivers, otherwise you may need to use an Active Adapter on the 3rd display to get it to function correctly on our latest drivers.
Utilising an active adapter instead of a passive adapter utilizes a small chip inside the adapter that converts the DisplayPort signal to a signal that is usable by a VGA/DVI/HDMI connection, while still maintaining the DisplayPort standard. Using a passive adapter just converts the DisplayPort output to a legacy/passive output.
For a list of certified adapters, you can refer to http://support.amd.com/en-us/recommended/eyefinity-adapters, as these are adapters that our certification team has tested with our cards and found them to be compatible with all AMD products. For reference regarding the difference between single-link and dual-link DVI adapters, the single-link has a maximum resolution of 1920x1200, while dual-link adapters (featuring more pins) can support up to 2560x1600. This relies on using a dual-link DVI wire as well, however.
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