[CentOS] 4 monitors with one graphics card and standard driver

Tue Apr 16 17:52:57 UTC 2013
Dale Dellutri <daledellutri at gmail.com>

I've just test an ATI FirePro 2460 graphics card on CentOS 6.4.  It
connects 4 monitors.
It worked with the standard radeon driver.  I was able to arrange the
monitors into my
preferred configuration (as a square array, 1 upper left, 2 lower left, 3
lower right, 4
upper right) simply by clicking System -> Preferences -> Display, and then
moving the
four monitor images.  This creates the file ~/.config/monitors.xml .

Moving windows among the monitors worked smoothly.  I did not install the
proprietary
ATI driver;  I don't need any of its features beyond what the standard
driver provides.

Some details:
  Dell Optiplex 9010, Small Form Factor (SFF) case requires SFF cards.
  CentOS 6.4 fully updated as of today.
  2.6.32-358.2.1.el6.x86_64 kernel
  xorg-x11-drv-ati 6.99.99 1.el6 x86_64
  BIOS shows the board in slot 1 (the blue connector) as "VGA Compatible"
  lspci shows
    01:00.0 VGA compatible controller:
    Advanced Micro Devices [AMD] nee ATI Cedar [FirePro 2460]
    Kernel driver in use: radeon
  No xorg.conf was created or required.
  4 Dell 2007FP monitors, each at 1600x1200 connected via DVI.

I used to use Matrox M9140 cards, but that requires the Matrox proprietary
driver which has not been updated for CentOS 6.4 as of today.

I also tested two other cards: ATI FirePro 2450 and NVidia Quadro NVS 420.
For each of these cards, the BIOS shows the card in slot 1 as a PCI Bridge.
lspci reports two identical video cards at 03:00.0 and 04:00.0.
Though it's easy to set up two screens properly, xinerama would probably be
required in an xorg.conf to get all four screens working properly.

-- 
Dale Dellutri