doesn't work on 2014 13" macbook pro retina

[kuobakuoba]

As title I tried it out and have no change And I also find an issue,not totally sure whether that's cause by this patch or not. I found out that the "kernel_task" eat up all of the cpu usage,and after I unpatch it turned to normal. Hope this imformation helpful. And want to ask that is this patch for any mac or just new 12" macbook retina?(come from 9to5mac's tutorial) thanks.

[Floris497]

Before the 9to5mac had an article i had no idea if it would work on 12".. So it works on all macs! I never heard of the kernel task taking anything other than normal.. I would recommend to reinstall the os.. If you can't find out what it is..

[kuobakuoba]

I manage to figure out that the kernel task issue is cause by disabling the SIP After the patch and enable SIP there's no such issue except that......it's still at 30Hz.QQ yet,thanks a lot.

(update:After reboot I find out I didn't enable SIP and have no issue(but still at 30Hz),I don't know why. )

[Floris497]

Apple + shift + 4 then press space and hover over the window you want to capture :) i recommend you to not put private info there in this way.

Moving on to the issue you have. Did you try using switchresx? Make an custom resolution. Try 40hz and 50hz as well!

[Floris497]

I can't read 4k or 3840x2160 in Chinese :p what resolution are you trying to use?

[kuobakuoba]

haha I remove the pic thx the suggestion I am running 3840x2160 at 30Hz and 1080p HiDPI I have tried switchres 3840x2160 at 50 and 52Hz according to internet tutorial.(not 40Hz yet but even if it work doesn't make a huge difference) But everytime I use a custom 50+Hz settings ended up black screen that I have to forced reboot. That drives me crazy.(have to go to bed XD) thanks.

[Floris497]

Do you have dedicated nvidia graphics? Then try that patch as well.. What kind of cable are you useimg? And what screen?

[kuobakuoba]

this is the model I'm running(so no dedicated graphics) and the Monitor I am using is Dell P2415Q via included mini display port to display port Cable.

[Floris497]

I remember that some dell monitors could only do exactly 30Hz and 60Hz.. For the rest your display has SST over DisplayPort.. What is great! I don't know why the patch isn't working.. It is patched im a 100% sure.. Did you try the other thunderbolt port.. Sometimes it makes a difference.

[kuobakuoba]

I just tried the other thunderbolt port...doesn't work lol. I'm pretty sure that this monitor can do 60Hz since the on screen menu shows that. (have no idea why it's up side down) I've tried MST off, primary and secondary and only secondary can show up at 30hz others just no signal. Again thanks a lot for your diligent help.😅

[Floris497]

It should be able to do it all without MST. This display should be able to do 60Hz.. Over SST. No sure what primary and secondary means here.. Could be it has a MST hub, so you can connect another monitor to it :p i would try all 3 options with both ports.. (I'm not joking, in some way I only got 60Hz working on 1 port of a 2015 MBP with nvidia)

[kuobakuoba]

I swich the MST off and the setting seems to be working.

But I cannot get any signal just black screen. I think that may be some dell driver issues or something. That means your patch seems to be working😅 I'll try to solve this myself. You're awesome appreciate your support.

[Floris497]

So you got 4k@60Hz now? Try using switchresx to change resolution :)

[kuobakuoba]

I use this setting and it immediately turned into black screen on both my internal and external display so I have to forced reboot. Is that normal that switchresx affects both screen even if I only change the external one?

[Floris497]

With this display you should not use 50Hz I think.. Could you try what happenes when you close your MacBook? Or when you boot it closed, and don't open it.

[kuobakuoba]

I've tried lid closed and closed reboot when I choose MST off but there's no signal at all. I noticed if I choose MST ON the frame rate of 1440p and above will be limited at 30hz on all switchresx resolution configurations(but every resolution work at 30hz). Choosing MST OFF will show every resoltion at 60hz but anything above 1440p won't work(the option changes according to the display MST setting) I also tried unpatch the patch then choosing MST OFF will only show 1440p at 60hz anything above simply disappear. (using a custom 50Hz show this,and 60hz will simply have no signal at all.I wonder if that's the hardware limitation of this mac)

[Floris497]

All I know is that some dell monitors can give trouble with this kind of things.. Have you tried another Mac to see if you get 60Hz working? It can be that other Macs can do it.. And your Mac can do it with a different display.. I do not keep a list of what hardware supports what..

[kuobakuoba]

I currently don't have any other mac or 4k monitor to get access to. I'll update this forum after I have any progress. Again thanks a lot man～u r very patient😅

[Floris497]

No problem, I'll let you know when something else comes to mind.

[tonatiuh]

Hey @kuobakuoba, I have the exact same Macbook pro retina model - not sure why this model has those issues if I have seen 2013 rmacbook pros to handle 4k correctly. I also have the same monitor.

I have been able to take the frame rate to 56HZ. Here's what I've done (not sure if the order matters):

• Setup SwitchresX
• Create the following custom resolution:

• Setup the patch:

  $ cd mac-pixel-clock-patch-V2/
  $ sudo ./IOKit-patcher.command md5
  $ sudo ./IOKit-patcher.command 

• Restart

Then once I restarted I went to switchresx and saw:

Then I went to the screen preferences and selected 56 Hertz as shown here:

Hope that helps. If you guys need anything else from my side, feel free to ask.

[tonatiuh]

Update:

• I have been able to make it run to 59HZ:
• You can see it enabled here:

One last recommendation, when you create the custom resolution to 59hz and restart, disconnect the monitor and don't connect it again until you apply the patch, otherwise, it's very likely that either the monitor or the computer will hang up. After applying the patch and restarting, when you plug the monitor again, you should be able to select 59hz successfully.

Note 60hz seems to not work, I tried it and SwitchresX marks it as "NTSC" and hangs up the computer when selected. For 59hz and above SwitchresX doesn't add the "NTSC" suffix.

[hyspace]

I have same macbook pro and tried on both Samsung U28E590D and LG 27UD68-P. I was only able to run on 50Hz instead of 60Hz, 56Hz and 59Hz are not working either. There is also a problem that after restart, I have to re-plug in the line to make the monitor work(awake from sleep seems fine). I wonder why this happened only on 2014 model. Hope it can be fixed some day.

[hyspace]

I also got some strange problem. When I'm using the display with 50Hz, some times the wifi will stop working. I'm sure it related to the monitor since it start to work again if I take the computer far away from the monitor. I'm not sure if this is related to the pixel patch or not though. I will try to connect to 5GHz wifi instead to see if it works.

[kuobakuoba]

Thanks @tonatiuh for the help. Apologize for being absence so long.😅 I have tried both settings you gave(56&59Hz). Both refresh rate did show in the system preference and I could choose either of them. But none of them worked just showed no signal.😩 50Hz wont work either...... Any thing below 50Hz the monitor seemed to be able to receive signal. Yet it showed refresh rate not supported just like the picture I posted above. I have given up trying. Thanks again to @Floris497 @tonatiuh.

[Floris497]

I have 2 of those monitors.. and the problem is that they use MST..

[kuobakuoba]

So this monitor really don't work right?? I have tried any MST settings.

[Floris497]

If you turn off MTS you will be limmited to 30Hz.. most probably a SST will work.. but not 100% sure