# cheapest nvidia graphics cards to support 3 monitors?

## m27315

I'd like to upgrade my dual-head setup to a triple-head setup, and I'd like to stick with nVidia.  The 3 monitors are 24" (1920x1080), and they have DVI and HDMI connectors.  My workload is primarily 2D work apps (coding, web-development, etc.).  Probably the only 3D acceleration I am using is KDE's eye-candy.  I don't need super-powerful cards, so I'd like to find the cheapest nVidia cards that will support 3 monitors.  I want to be able to drag windows from any monitor to any other monitor, and maximizing a window should only consume a single monitor - not all 3.  I don't mind paying a few dollars more to get something quieter, cooler, newer, more robust, or more powerful.  So, price is important, but I'm not trying to pinch every penny to the exclusion of all other features.  (CUDA would be a nice bonus, as I may try to use it in the future.)

(I understand you need 2 cards based on nVidia's support page.  Since these are the 3D surround requirements, maybe 2D surround's requirements are less?)

Any suggestions?  Bonus points for Black Friday or Cyber Monday specials....  :Wink: 

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## krinn

Well, you need 2 cards, so i would just pickup 2 that are SLI ready. the power/price will stay upto you. Some manufacturers sometimes do that kind of card with nvidia chip that handle more than just 2 screens, but using a pcb with 2 chips on it, like this one a 580 base : http://www.amazon.com/Galaxy-Technology-Mini-HDMI-Graphics-58NLH5HS3PXZ/dp/B004K1EQLO

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## chithanh

Apart from the dual-GPU Quadro cards, very few NVidia cards support 3 monitors (Prices are from Newegg):

EVGA GTX 460 2Win ($390) and 560 Ti 2Win ($520)

Zotac 460 3DP ($225) and 560 MultiView ($230)

Galaxy 560 Ti MDT ($310)

A graphics card independent solution is the Matrox TripleHead2Go adapter ($300).

Using dual-GPU configurations used to be troublesome on Linux, newer NVidia drivers support the BaseMosaic option which improved the situation somewhat. Note that 2D/3D surround gaming is not supported in Linux.

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## m27315

I don't mind 2 cards.  So, will any 2 cards that support SLI provide the 2D Surround?  Or, does 2D Surround not work in Linux at all?  (I don't care about gaming.)  Does anybody have a cheap, working 2D Surround setup in Linux?  I was hoping to buy 2x $50-$75 cards...

Thanks!

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## chithanh

NVidia Surround is not supported in Linux, neither 2D nor 3D. The system requirements explicitly mention Windows 7.

However the BaseMosaic function is a kind of replacement for 2D surround. It requires cards that work in SLI together. So find the cheapest card that supports SLI and buy two of them.

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## krinn

what's that 2D surround thing compare to two screens ? (eheh some kind of commercial stuff, but i suppose they add at least 1 thing to justify the name)

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## m27315

Thanks, chithanh.  I am ordering two cards now.  I'll report back, once they are setup.

 *krinn wrote:*   

> what's that 2D surround thing compare to two screens ? (eheh some kind of commercial stuff, but i suppose they add at least 1 thing to justify the name)

 

My poor understanding is that the 2D surround allows you use 3+ monitors like many of us are accustomed to 2 monitors working:  You can drag windows from one screen to another, as they are all connected.  However, maximizing any windows causes the window to consume 1 monitor, not all 3+.  Without 2D Surround (or BaseMosaic), then you cannot drag windows from one screen to another, or maximizing consumes all monitors.  I could be wrong, so take this with a huge grain of salt.

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## Jaglover

Can't xinerama do that?

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## m27315

 *Jaglover wrote:*   

> Can't xinerama do that?

 

I could be wrong here, but I think 2D Surround (or, BaseMosaic ?) is preferable over Xinerama for 3+ monitors as TwinView is preferable over Xinerama for 2 monitors.  (I recall Xinerama being slow and buggy in my setups circa 2000.  Maybe it was just me?)  I'm still in the early stages of research, so I could be way off...  I was hoping for the voice of experience, which I believe I have gotten from here.  If I have misunderstood, please correct me.

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## Jaglover

Maybe, I've been using Xinerama over TwinView for so long time I even do not remember why I made this choice. All I can recall is there was a reason.

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## chithanh

With xinerama you lose 3D acceleration. With BaseMosaic you get other problems (tearing etc.), but it is not as bad as having an unaccelerated desktop.

Both however are inferior to Windows multi-GPU support and/or single GPU multi-monitor setups.

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## Jaglover

That's news for me, could not find any confirmation though. GoogleEarth works fine, a quick google gave this claiming 3D works with proprietary drivers. I'm really interested in VDPAU only and that definitely works.

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## m27315

So, I opted for 2 nVidia 450 GTS cards, roughly $100 each on Black Friday.  Each card has 2 DVI ports, but neither has all 3, so I am trying to combine them to support my 3 monitors.  Xinerama works ok, except I can definitely tell a graphical slowdown in just moving windows around on the desktop.  It's not unbearable, but it leaves me wanting to sample BaseMosaic.  I googled for examples, and I could not find a complete example xorg.conf.

Can anybody submit a relevant snippet, so I can experiment with BaseMosaic in my setup?

Curiously, nvidia-settings does not show BaseMosaic as being an option in any of its panels.  Maybe this is a bad sign?

Thanks!   :Smile: 

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## chithanh

The BaseMosaic must be enabled in the Driver section of xorg.conf

I think you can use "nvidia-xconfig --base-mosaic" to generate one for you.

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## m27315

 *chithanh wrote:*   

> I think you can use "nvidia-xconfig --base-mosaic" to generate one for you.

 

After experimenting, I think BaseMosaic is working with my 2x450 GTS cards, because KDE4's kwin 3D (?) compositing desktop effects (like, cover flow application switching, desktop cube switching, etc.) are working correctly.

I moved my old xorg.conf out of the way and created a new one with:

```
nvidia-xconfig --base-mosaic --metamodes="GPU-0.DFP-3: 1920x1080+0+0, GPU-0.DFP-0: 1920x1080+1920+0, GPU-1.DFP-2: 1920x1080+3840+0"
```

I tweaked the results a little.  The main thing I did was explicitly disable Xinerama, which seemed to be activated by default for some reason.  Maybe because it automatically found multiple cards and monitors?  I dunno...

Anyway, the following xorg.conf allows me to use kwin's compositing desktop effects.  And, if I don't disable Xinerama, kwin reverts to no effects.

Thanks for the help!

Any suggestions for improvements or experimentation?  I'd like to get the most out of these 2 cards.  BTW, I do have the cards connected in hardware via the SLI bridge connector.  And, I was never able to convince nvidia-settings to expose the Base-Mosaic, or even the SLI settings directly.    :Confused: 

Thanks!

```
# nvidia-xconfig: X configuration file generated by nvidia-xconfig

# nvidia-xconfig:  version 290.10  (buildmeister@swio-display-x86-rhel47-07.nvidia.com)  Wed Nov 16 18:47:40 PST 2011

Section "ServerLayout"

    Identifier     "Layout0"

    Screen      0  "Screen0"

    InputDevice    "Keyboard0" "CoreKeyboard"

    InputDevice    "Mouse0" "CorePointer"

    Option         "Xinerama" "0"

EndSection

Section "Files"

EndSection

Section "InputDevice"

    # generated from data in "/etc/conf.d/gpm"

    Identifier     "Mouse0"

    Driver         "mouse"

    Option         "Protocol"

    Option         "Device" "/dev/input/mice"

    Option         "Emulate3Buttons" "no"

    Option         "ZAxisMapping" "4 5"

EndSection

Section "InputDevice"

    # generated from default

    Identifier     "Keyboard0"

    Driver         "kbd"

EndSection

Section "Monitor"

    Identifier     "Monitor0"

    VendorName     "Unknown"

    ModelName      "Unknown"

    HorizSync       28.0 - 33.0

    VertRefresh     43.0 - 72.0

    Option         "DPMS"

EndSection

Section "Device"

    Identifier     "Device0"

    Driver         "nvidia"

    VendorName     "NVIDIA Corporation"

EndSection

Section "Screen"

    Identifier     "Screen0"

    Device         "Device0"

    Monitor        "Monitor0"

    DefaultDepth    24

    Option         "BaseMosaic" "True"

    Option         "MetaModes" "GPU-0.DFP-3: 1920x1080+0+0, GPU-0.DFP-0: 1920x1080+1920+0, GPU-1.DFP-2: 1920x1080+3840+0"

    SubSection     "Display"

        Depth       24

    EndSubSection

EndSection

Section "Module"

    Load "extmod"

    Load "dbe"

    Load "type1"

    Load "freetype"

    Load "glx"

EndSection
```

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## m27315

Update:  I read somewhere else about someone complaining that the dual-card setup with BaseMosaic does a "sucker punch" to Xorg occasionally, either locking up or temporarily freezing the system.  And, after several weeks of using a this dual-card setup with BaseMosaic, I can confirm this is true.  Either one or all of my KDE plasma applets are related to the root cause, because if I remove all of them, it helps to dramatically reduce the system lock-ups and freezes.  However, my system still feels unstable.

I am hoping that newer versions of Xorg, nvidia-drivers, or KDE components help this problem.  Currently, I am using:

```
KDE:  4.7.4

xorg-server:  1.11.3

xorg-x11:  7.4-r1

nvidia-drivers:  290.10
```

My setup works, and I would probably try this again - or maybe I'd go for the 3 monitors on one card, but it feels fragile, and I am not thrilled with it.  I would try another option, if I knew what to try.

I am open to any suggestions, if someone stumbles across this.

Thanks!

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## chithanh

You could try to downgrade xorg-server to 1.10 (rebuild x11-drivers/* afterwards), I have seen several reports that the proprietary AMD and NVidia drivers don't work properly with that version.

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## chithanh

One addition: running 3 monitors off one NVidia card has become easier now. Galaxy has released the G210 MDT X4 which is a single-GPU card for four monitors. I don't know about the driver support for Linux though. Zotac has released the ZT-DP2HD which turns one DisplayPort output into two HDMI outputs (extended desktop mode) and poses to the graphics card as one single large monitor.

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