So I have a new HP workstation with an AMD FirePro W5100 card (specs and other details below). Replaced an older system where 4 monitors were working fine.
The FirePro W5100 has 4 DisplayPort outputs, but I can only seem to get any combination of 3 monitors to work (the 4th always just gives a "no signal" message and goes black). I was under the impression that I could run 4 monitors off of this, but I'm wondering if there's something wrong with my combination of adapters. The monitors only have DVI and VGA ports, no native DisplayPort connections, so I'm using active displayport -> DVI adapters.
The AMD FirePro software shows a 4th monitor as disabled. If I try to extend to it, FirePro software gives me a message that I have to disable one other monitor before I can enable that one. I get the same thing if I try to enable the 4th monitor in Windows 7 display settings (just gives me an "Unable to save display settings" error).
I know the monitors themselves are fine because I can get any combination of 3 monitors in any combination of 3 ports to work. The adapters I'm using are all identical. So basically, I can only have 3 monitors running at a time. Windows 7 and the FirePro software both acknowledge that 4 monitors are connected, but I can't enable the 4th one.
Am I missing something here? Should I be able to run 4 monitors on this card the way I'm trying to do it?
Some other system specs:
Windows 7 Pro SP1
Intel Xeon E5-2650 2.30GHz
AMD FirePro W5100
LG Flatron L2000CP monitors (all 4 monitors are the same model)