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U2417H, DP 1.2 daisy chain mirrors, but does not extend.

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I have 2 new dell U2417H which I am trying to connect to my machine via daisy chained displayport. The computer I have it connected to is an HP 400 G3 SFF.  I have confirmed that this computer supports MST via displayport. The current configuration of the connections are as follows:

CPU DP > First Monitor mDP input > First Monitor DP output > Second Monitor mDP input

Both monitors currently have displayport 1.2 enabled. I have done factory resets to both just to be sure. 

Even though the display is mirrored on both monitors, windows does not detect more than one monitor attached.  I am running a fresh install of windows 10 64 bit (I have also tried it on an identical machine fresh out of the box with the same result). I have updated the video drivers to the latest release. It is an onboard Intel HD 530 which supports multistream via displayport. 

Is there any issues with using mDP ports instead of full sized form factor displayports?  Currently The monitors only came with mDP to DP cables and the new cables are on the way, but are a couple of days away. From what I can tell, using mDP shouldn't be an issue because there is no difference other than they are different form factors.

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RE: U2417H, DP 1.2 daisy chain mirrors, but does not extend.

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I had this exact same issue with Dell U2717D monitors.  The monitors were mirrored and showed up in the display manager as one single monitor.  I played with enabling/disabling DP 1.2 on the second monitor to no effect.  Finally I found out that there was another setting in monitor configuration that was simply called "MST".  Evidently this is called "Multi-Stream Transport".  Once I ENABLED MST (in addition to DP 1.2) on the first monitor, the displays un-mirrored themselves and Windows treated them as separate monitors.  Enabling DP 1.2 and MST on the second monitor allowed me to daisy-chain a third monitor.  They are all recognized as 3 separate monitors and can have independent resolution settings.  At least for me, MST was the key.  The MST setting on the U2717D is under DISPLAY -> MST.  For me, at least, this fixed the issue of the displays mirroring while daisy-chained.

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RE: Dell U2417H displayport daisy chain mirrors, but does not extend.

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The second in the chain should be set to MST/DP 1.2 Off. I would also swap them (current primary U2417H change to secondary U2417H) to see if the issue is the same. No, primary U2417H on mDP should work.


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RE: Dell U2417H displayport daisy chain mirrors, but does not extend.

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Just switched the secondary to the primary with the same configuration, but it has the same result.

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RE: Dell U2417H displayport daisy chain mirrors, but does not extend.

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Not sure what else you can do but test them on another system with a dedicated video card that has DP or mDP and also testing with a DP to DP cable on that HP. Where did you find HP documentation that stated its onboard DP out port supports DP 1.2 daisychaining? That is not mentioned here or here ?


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RE: Dell U2417H displayport daisy chain mirrors, but does not extend.

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Tested with DP to DP, same result. It does mention it on the first PDF you linked. On page 22 it is listed under the 400 G3 SFF (small form factor), which is the model I have:  

1 VGA

1 DisplayPort

with multi-stream

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RE: Dell U2417H displayport daisy chain mirrors, but does not extend.

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I do not think that  the monitors are at fault here. Then the only other option is to test them on another computer. Preferably a computer with an added video card that has DP out or mDP out. Also contact HP support and ask if they successfully tested that system in a two monitor DP 1.2 daisychain.


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RE: U2417H, DP 1.2 daisy chain mirrors, but does not extend.

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I had this exact same issue with Dell U2717D monitors.  The monitors were mirrored and showed up in the display manager as one single monitor.  I played with enabling/disabling DP 1.2 on the second monitor to no effect.  Finally I found out that there was another setting in monitor configuration that was simply called "MST".  Evidently this is called "Multi-Stream Transport".  Once I ENABLED MST (in addition to DP 1.2) on the first monitor, the displays un-mirrored themselves and Windows treated them as separate monitors.  Enabling DP 1.2 and MST on the second monitor allowed me to daisy-chain a third monitor.  They are all recognized as 3 separate monitors and can have independent resolution settings.  At least for me, MST was the key.  The MST setting on the U2717D is under DISPLAY -> MST.  For me, at least, this fixed the issue of the displays mirroring while daisy-chained.

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RE: U2417H, DP 1.2 daisy chain, Apple MacBook Pro?

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I tried the same, but didn't work. I am using it with Macbook Pro. Is there a solution for Macbook pro?

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RE: U2417H, DP 1.2 daisy chain, Apple MacBook Pro?

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Unknown by Dell. As you can see in the image below taken directly from the monitor page, the Apple proprietary hardware, operating system (including Windows bootcamp), cabling, and drivers were not tested/validated by Dell.

U2417H.JPG

Since we at Dell are not trained in the usage of the Apple hardware and operating system, you should ask the Apple users on the Apple Forum for troubleshooting and cabling opinions.


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RE: U2417H, DP 1.2 daisy chain, Apple MacBook Pro?

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You will find DP chaining is unsupported by Apple, used to work in older versions of OS X, but like everything with Apple they think they know best 😉

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