The multiple monitor experience on Linux traditionally was very arcane and difficult; it would involve editing text configuration errors, trial-and-error, picking the right Linux GPU driver, and various other steps to get a working multi-monitor desktop. Since then there's been RandR 1.2+ and major improvements to all of the important Linux desktop graphics drivers -- both open and closed-source. How is the Linux multi-monitor now when using a modern distribution and the latest graphics cards that can drive four monitors simultaneously? Let's find out! Up for testing today are NVIDIA and AMD graphics cards using both the open and closed-source drivers while using DVI, DisplayPort, and HDMI displays.
After last week delivering the first Ultra HD 4K Linux graphics card and driver tests I decided to follow-up on that with some quad-monitor testing. The latest NVIDIA (GeForce 700 series) and AMD (Radeon R9 200 series) graphics cards were tested from Ubuntu 13.10 x86_64 while trying out their respective open and closed-source drivers. On the NVIDIA binary side was the NVIDIA 331.20 release while on the AMD side was the Catalyst 13.11 Beta v9.4 release; both of which are the latest at the time of testing. The open-source driver testing happened from the Linux 3.12 kernel with Mesa 10.1-devel from the Oibaf PPA and recent Git snapshots of the xf86-video-nouveau and xf86-video-ati DDX drivers.
The monitors used for testing were four of the 1920 x 1080 displays in my office. The displays weren't identical and included two Dell, one ASUS, and one ViewSonic unit. Two of them were 22-inch displays and the other were 24-inch displays. Two of them were used with DVI connections while the other was using DisplayPort and the other was configured for HDMI. These varying 1080p monitor attributes aren't ideal for a single system quad-monitor configuration, but the rest of the time these monitors are all driving four separate systems simultaneously in tests being carried out at Phoronix. The configuration serves fine for just some performance and feature testing and isn't used for any real gaming purposes. All the monitors are setup on Type Supply LCD stands. I have multiple Type Supply LCD stands and continue to like them a lot, they're built well, still working great over the years, and cost much less than the products from the likes of Ergotron.
Up for testing first were the NVIDIA GeForce GTX 700 series on the proprietary driver. The tested graphics cards included the GeForce GTX 760, GTX 770, GTX 780 Ti, and GTX TITAN along with the GTX 680. All of these higher-end graphics cards with plenty of video memory and all sporting dual DVI, DisplayPort, and HDMI connections had no trouble driving the four 1080p displays simultaneously. The AMD testing was the Radeon R9 290 and other recent high-end Radeon GPUs.