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I have plus E-Port on my E5450 and i have some problem with DP Connection.

When i try to use DP on the e-port, monitor say display port no signal.

In window 10, same HW config, dp out 4K @60Mhz on my asus monitor . ( i exclude cable problem)

When i boot with lcd close, dp connected, i see boot screen at mojave statrtup but it never switch to graphical mojave login screen on my monitor.

When i boot with lcd open, evry thing work but i have display port no signal on monitor

I inspect ioreg entrys, on FB0 is use for ldc (monitor applebacklightdisplay), FB1 and FB2 type DP and monitor is reconize as appledisplay but allways no signal on monitor (with DP input on it), with this config, when i plug HDMI monitor work correcly.

When i change connection it appear be correct in ioreg igpu framebuffer and monitor ( value change automaticaly when i change cable connector position on e-port.

Has anybody idea how to find issue ? I have read a lot of page on the subject but i don't find the way to find solution ( probably due to knowledge for this subject ), I have update to last cover version but it's the same.

I my config, everything work perfecly exept this point.


Attached, Dump and ioreg


In advance, thanks a lot for your help. 

debug_19326.zip ioreg.dump.ioreg

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I have spend lot of time in literature and post about this subject, i'm very disapointed, i'can't find the solution......

I'dont know what is wrong. I spend lot of time with Hackintool to try to find an issue but nothing ;-(

perhaps somebody can help me, i will be very thankful. ( @Jake Lo , @Hervé i thing you are the best to help me please ......)

I put here my last EFI and my iore (I have change the dp port on my docking station, you can find then change)

Thanks thanks a lot.....



IOREG.save.ioreg EFI.zip

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I don't have any E5450 at hands but I have an E7250 until the end of the week. I don't have a mini-DP cable and a DP screen for testing but I can try DP output through my E-Port dock out to HDMI via an adapter.


You may need to change the default FB #/port# of the BDW frame buffer for your DP output port to work although it's unlikely. You use BDW layout 0x16260006 which defines the following output ports:

06002616 01030303 00002002 00005001     --> layout 0x16260026, 3 x output ports
00000060 D90A0000 D90A0000 00000000
00000000 00000000
00000800 02000000 30020000              --> FB #0/port #0, built-in LCD
01050B00 00040000 07050000              --> FB #1/port #5, DP output (but usually HDMI port)
02040B00 00040000 07050000              --> FB #2/port #6, DP output


Looking at your posted IOReg outputs, I can clearly see your external display attached to [email protected]/port #6. As such, I guess your problem is highly likely to be a 4K-related problem more than anything else.


I don't have a 4K screen myself so I've never had any 4K-related issue to resolve but I believe the issue of black screen on 4K displays is quite common. I also understand there is an existing fix (or fixes?) for it, like using boot parameter -cdfon.



Now, looking at  the EFI folder of post #1, I could see 2 x Clover config files:

  1. config.plist (which is the default name of Clover's config) is empty and therefore I assume you cannot be using it.
  2. config_ok_ref.plist contains the following typo in the Graphics properties injection:
                </data                         --> typo! it should be "</data>", the final ">" is missing

That same typo is also found in the 2 x Clover config files of the EFI folder of your 2nd post...


You need to correct this with a text editor like TextEdit or Clover Configurator; whether it'll fix the issues you encounter, that I cannot say for sure but I certainly smell a fish...


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I Hervé,


Tanks a lot for you help, i follow you guideline and with the literature i find the solution to my problem, with the typo correction and the -cdfon at clover options and the use of switchResX, everything wotk great !

I'm very happy with this config !.

Now i try to install osx on my 5580 (professionnal pc) to compare the perf. and chose with i use for mojave.


Thanks a lot for you help



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