Im trying to help a friend setup his 3 monitor display. We cant seem to get more then two monitors working... I can swap in-between monitors all day long, so they all work fine, and all the connectors seem to be working... But It just will not display more then two at once, here is a link showing what happens when I try to enable a third.
How are the monitors connected? What gpu? For eyefinity you really need to connect your 3rd monitor via displayport 'ACTIVE' adapter. There's one person in here that claims to have gotten eyefinity to work with passive adapters, but no word on how he did it. So until I find a way with passive adapters, I will recommend active.
From the video it looked like the 3rd monitor was a lower res is this true? If so all three monitors must be the same resolution or you will not be able to do Eyefinity. And as the person above me said you need at least on monitor on a DisplayPort or Active DisplayPort adapter.