3 Monitors, 2 GTX570, One monitor doesn't work with 340.24...

Hello all…

I just finished building a new advanced workstation for visualization applications under Linux. The system has two GTX570 cards (NOT in an SLI configuration) and three monitors attached - two monitors on card 1, and one monitor on card 2. When the system first booted under Fedora 20, it loaded the crappy Nouveau driver, and all three monitors were seen as a single X desktop (Screen0), and worked perfectly, albeit with crappy graphics and no 3D acceleration.

When I disabled Nouveau and installed a real NVIDIA driver (340.24), the first two monitors (attached to card 1) worked just fine as X Screen0. I added card 2 to the xorg.conf file, and I was able to activate the third monitor, but regardless of my configuration, it always shows up as X Screen1.

I’m a UNIX engineer with almost 25 years of experience, so I’m at my wits end. I’ve built this configuration hundreds of times on Sun, HP, and IBM hardware, and I’ve never had problems.

Does anyone have a working xorg.conf file that shows two (or more) cards working with 3 (or more) monitors as a single X screen? I need to be able to drag application windows between all three monitors, so using two different X screens isn’t an option. The key here is the single X screen.

By the way, I can’t see an option to attach the nvidia-bug-report output, but I’d be happy to email it to anyone interested in helping. It would be really nice if NVIDIA stepped up and provided real support for Linux - I’ve posted this same message on various forums starting months ago, and nobody has ever responded.

Please help!