When planning a triple or quad monitor setup with Windows 7 and an ATI FirePro™ 2460 Multi-View Professional Graphics card, read the small print.
In my case, reading the following small print from the data sheet carefully would have saved some time:
Important: When using mini DisplayPort-to-singlelink DVI adapters, quad output is divided into two pairs (displays 1 and 2, and displays 3 and 4). The displays used in each pair must be identical (with the same manufacturer and model number) and must be identically configured (with the same resolution)...
In my case, I had two identical Dell 19" displays and one of the new energy-efficient G2210 displays. I paired the two 19-inchers on DisplayPort connectors 1 and 2, and put the G2210 on the third DisplayPort connector. All used the DisplayPort-to-singlelink DVI connectors that came in the box with the card.
Problem: In Windows 7 x64, when trying to configure multiple monitors in the control panel (Control Panel\Appearance and Personalization\Display\Screen Resolution), I kept getting the message "Unable to save display settings" when I tried to extend the desktop.
Solution: What was meant by that cryptic message was really "the two displays you think are identical really aren't". Sure enough, one of the 19-inch displays was an UltraSharp 1901 and the other was an UltraSharp 1905. They look identical and have the same native resolution and connectors. I scuttled around, found another 1905, and swapped it in. When I powered up, sure enough, with two UltraSharp 1905's the control panel doesn't complain at all.
Did I mention the 2460 is fanless? Yum.