# Mini Display Port on ThinkPad T530

## toydarian

Hey guys,

I got a question, that bothers me for some time now and I have not been able to find an answer on the internet yet.

So perhaps, someone has a setup similar to mine and is able to help me finding the answer.

I got an ThinkPad T530 with an Intel i7 with integrated Intel HD Graphics.

```

00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09) (prog-if 00 [VGA controller])

        Subsystem: Lenovo Device 21f5

        Flags: bus master, fast devsel, latency 0, IRQ 40

        Memory at f0000000 (64-bit, non-prefetchable) [size=4M]

        Memory at e0000000 (64-bit, prefetchable) [size=256M]

        I/O ports at 4000 [size=64]

        Expansion ROM at <unassigned> [disabled]

        Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-

        Capabilities: [d0] Power Management version 2

        Capabilities: [a4] PCI Advanced Features

        Kernel driver in use: i915

```

As well as an nVidia graphics Card that is deactivated in the BIOS (saves power and is not needed).

The ThinkPad has a VGA port as well as a Mini Display Port.

The VGA Port works well, but the MDP is not shown by xrandr.

Here is the xrandr output:

```

Screen 0: minimum 320 x 200, current 2944 x 1280, maximum 32767 x 32767

LVDS1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm

   1920x1080      60.0*+   50.0  

   1400x1050      60.0  

   1280x1024      60.0  

   1280x960       60.0  

   1024x768       60.0  

   800x600        60.3     56.2  

   640x480        59.9  

VGA1 connected 1024x1280+1920+0 left (normal left inverted right x axis y axis) 338mm x 270mm

   1280x1024      60.0*+   75.0  

   1152x864       75.0  

   1024x768       75.1     60.0  

   800x600        75.0     60.3  

   640x480        75.0     60.0  

   720x400        70.1 

```

The question is: Is it possible that the MDP is only connected to the nVidia card and thus works not, if the nVidia is deactivated, or did I miss any driver or something so the MDP is not supported.

Thanks for your replys!

Greets

toydarian

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## eyoung100

Visit the Bumblebee Project

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## toydarian

Hi eyoung100,

Thank you for your response.

The Problem is, I don't want to use the nVidia.

It would just be nice to know, if I made a mistake or if this MDP is hardwired only to the nVidia and can't be used with the Intel HD Graphics.

Greets

toydarian

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## eyoung100

See Neddy's Post for an explanation of what Optimus is.  Whether you want to use it or not, you're stuck enabling it to get that Port working...

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## toydarian

 *eyoung100 wrote:*   

> … Whether you want to use it or not, you're stuck enabling it to get that Port working...

 

Well, that's the question. Am I really stuck enabling it?

I doubt that because

- The VGA Port works fine.

- There is the same model without the nVidia (and Optimus) that has a MDP, too.

So why would someone build a Notebook with and MDP, an Intel HD 4000 but without the nVidia, where the MDP can be used but sell the same model with a MDP, an Intel HD 4000 and a nVidia but in that case prevent you from using the MDP if your nVidia is disabled?

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## eyoung100

 *NeddySeagoon wrote:*   

> The Intel one is a complete graphics system. It can write new images in the pixel buffer and read the pixel buffer out to the dispaly. 
> 
> The nVidia graphics can only write new images in the pixel buffer. It has no way to get the pixel buffer onto the screen. 
> 
> This means that for low power/performce you use the Intel system. 
> ...

 

See this Photo, and this NVIDIA info site.

The Blue Dot = intel.

The RedDot = NVIDIA

Green Dot = Optimus Driver Software

In Low to Average Power, the Blue Dot creates the Pixel Buffer  :Arrow:  Sends the Buffer to the Intel Graphics Bus   :Arrow:  Intel Draws Output on Screen.

In Situations Where Graphics are in High Demand  :Arrow:  Battery Saver Disabled  :Arrow:  NVIDIA Draws the Pixel Buffer   :Arrow:  NVIDIA sends the Buffer to the Intel Graphics Bus  :Arrow:   Intel Draws Output on Screen.

This works because the CPU Power in the NVIDIA GPU does all the Pixel Manipulation , and once rendered only needs intel to output it, therefore the NVIDIA Card has no output buffer, unless both cards work in tandem.  That is why the system cannot power on the MDP Port unless the Optimus Driver is installed, because it bridges the Highend Pixel Buffer you Paid for with the Intel Video Chipset that is default in all "pure intel systems"  The driver software only worked in Windows until the Bumblebee Project.

In your first Example, the MDP Port is Connected to "all intel parts" and no bridging software is needed.  In the Highend Model, the MDP input is wired to the NVIDIA, but since the output buffer doesn't exist, the MDP output is still wired to the Intel.  The NVIDIA isn't disabled, it just isn't "turned on" until the Optimus Driver Software is installed.  See The Bumblebee Wiki

 *Quote:*   

> Welcome to our wiki!
> 
> Many recent notebooks with a discrete nVidia card in it and an i3/i5/i7 processor use the nVidia Optimus technology to improve battery life. Unfortunately, this software solution is only available in Windows 7 and later.
> 
> The Bumblebee Project is a set of tools developed by people aiming to provide Optimus support under Linux (legacy nVidia hybrid graphics is supported too) while waiting for kernel and drivers to support these notebooks.

 

Software Solution means Windows Only Driver...

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## toydarian

Thank you, now I understand how this optimus thing works, at least.

Why every output except the MDP works without the NVIDIA, I still don't understand, but I think, I just have to accept that.

Last questions:

- Do I have to enable OS detection for Optimus in the BIOS?

- Does it suffice to emerge the nouveau driver, config the XServer and start the bumblebee deamon to use the MDP?

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## eyoung100

I dont have an Optimus Laptop, but I would imagine No to the first, and yes to the second.

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