cannot connect centos (dell precision) laptop to 2 external monitors (but I can connect to 1 external monitor)

Question

This is my first post here and hope I am following the rules of the forum. I reviewed Connecting 2 External Monitors to a Laptop? and confused with hardware terminology to figure out if my Dell Precision requires additional hardware or additional software or just some configuration.

I cannot make Linux(centos 6.5) connect to 2 external monitors. I was able to connect to 1 external monitor by running

 $xrandr --auto --output DP-0 --right-of LVDS-0

Here are the display properties

  $xrandr

  Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 16384 x 16384
  VGA-0 disconnected (normal left inverted right x axis y axis)
  LVDS-0 connected 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x         194mm
1366x768 60.0*+ 40.1
DP-0 connected (normal left inverted right x axis y axis) 1920x1080 60.0 + 1440x900 59.9
1280x1024 60.0
1280x800 59.8
1152x864 75.0
1024x768 70.1 60.0
800x600 60.3 56.2
640x480 59.9
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 connected        1920x1080+0+0 (normal left inverted right x axis y axis) 
477mm x  268mm 1920x1080 60.0*+      1440x900 59.9
1280x1024 60.0
1280x800 59.8
1152x864 75.0
1024x768 70.1 60.0
800x600 60.3 56.2
640x480 59.9
 DP-3 disconnected (normal left inverted right x axis y axis) 
DP-4 disconnected (normal  left inverted right x axis y axis)
DP-5 disconnected (normal left inverted right x axis y axis)
DP-6 disconnected (normal left inverted right x axis y axis)

Edit

I tried the following commands (and nothing happened)

 $xrandr --auto --output DP-0 --right-of DP-2

Here is the info on the vga card

 $lspci | grep -E "VGA" 
 01:00.0 VGA compatible controller: NVIDIA Corporation GF108GLM [Quadro 1000M] (rev a1)

And more on VGA

 $sudo lspci -v -s 01:00.0 

 01:00.0 VGA compatible controller: NVIDIA Corporation GF108GLM [Quadro 1000M] (rev a1)  (prog-if 00 [VGA controller])
 Subsystem: Dell Device 04a3
 Flags: bus master, fast devsel, latency 0, IRQ 43
 Memory at dc000000 (32-bit, non-prefetchable) [size=16M]
 Memory at d0000000 (64-bit, prefetchable) [size=128M]
 Memory at d8000000 (64-bit, prefetchable) [size=32M]
 I/O ports at 7000 [size=128]
[virtual] Expansion ROM at dd000000 [disabled] [size=512K]
  Capabilities: [60] Power Management version 3
 Capabilities: [68] MSI: Enable+ Count=1/1 Maskable- 64bit+
 Capabilities: [78] Express Endpoint, MSI 00
 Capabilities: [b4] Vendor Specific Information: Len=14 <?>
 Capabilities: [100] Virtual Channel
 Capabilities: [128] Power Budgeting <?>
 Capabilities: [600] Vendor Specific Information: ID=0001 Rev=1 Len=024 <?>
 Kernel driver in use: nvidia
Kernel modules: nvidia, nouveau, nvidiafb

Can I connect to 2 external monitors and extend the display just by configuring? If not, what is the reliable/easiest hardware/software I have to buy

****EDIT**** -Model is M4600 (Dell Precision); complete specs are here (I assume my laptop support all these) http://www.dell.com/downloads/global/products/precn/en/precision-m4600-specsheet.pdf

-VGA specs as per above specs sheet:

Graphics2 • AMD FirePro M5950 Mobility Pro with 1GB GDDR5 dedicated memory • NVIDIA Quadro 1000M with 2GB GDDR3 dedicated memory • NVIDIA Quadro 2000M with 2GB GDDR3 dedicated memory

Display Options • 15.6" HD(1366x768): anti-glare, LED-backlit • 15.6" HD(1366x768): multi-touch (supports stylus / four finger simultaneous touch), LED-backlit • 15.6" FHD(1920x1080): UltraSharp™, wide view, anti-glare, LED-backlit, Premium Panel Guarantee5 • 15.6" FHD(1920x1080): UltraSharp™ with PremierColor technology, IPS, wide view, anti-glare, LED-backlit, Premium Panel Guarantee5

-There is HDMI port (behind); I work for startup (so hopefully what I have is business grade); could not figure our display port (but let us assume it there)

-Also I am using docking station where my 2 monitors are connected to (I tested 2 external monitors working on this docking station from a DIFFERENT windows laptop and I am trying to do it for this centos laptop now)

Can it be as simple as a centos shell command to hook up the laptop to 2 monitors (if so what is that command)

Answer 1

This is a very complex question though I realise you will think it shouldn't be.

Firstly, all laptops (bar a very few exceptions) are designed around Windows not Linux so experimentation is best done in Windows.

Next, you've only listed the family not the model of laptop. Even within a family, the internal graphics capability can be wildly different. Indeed, often the manufacturers part number is required to work out the exact components used. Again, this will make a big difference.

If the laptop is a consumer model and reasonably new, it is likely that it will only support 2 monitors natively. Beyond that, you will need external hardware. The link you provided talks about hardware from Matrox & I'm not even sure you can still get them. Commonly, you may find that external USB "docking stations" will provide the capability for an additional monitor.

If the laptop has both VGA and another, digital output such as HDMI (typically consumer grade) or Display Port (typically business grade), it is possible that you might be able to drive two monitors from the digital output. It is a toss-up as to whether doing so would disconnect the VGA port.

For example, the Lenovo ThinkPad X200 series machines (at least from the 220 onwards) are capable of driving both the internal screen and three external monitors IF you have the docking station. You can use the docks VGA and Display Port and the laptops Display Port. The Lenovo ThinkPad Yoga however, only appears to support 2 external monitors (though maybe the full dock will change this).

In any case, you shouldn't expect too much from multiple external monitors as the bandwidth available to them is likely to be limited.

Your best bet is to try some external USB docking stations in a friendly PC shop.

Answer 2

Relying to xorg, DVI exits are called DVI-0 (the first), DVI-1 (the second) and so on. Internal VGA is going to be called VGA-0 and the external will be called VGA-1. Beware, that there may be TV-0 and TV-1. All these exits should be addressed one by one within the Xorg.conf, meaning that each configuration should appear including, the device, the exit and the preferred modesettings. Each step has to be tested alone per connection before adding another device.