Mac Pro Late 2013 and Samsung 4k monitor problem

Well, you could try the CVT-RB timing that I gave for 50 or 54 or 55 or 56 or 57 Hz. Just replace the <data> line.

Does the display have onscreen controls that show the vertical and horizontal refresh rate? If so then make sure those values match the timing you're using.

Maybe a higher quality DisplayPort cable would help? Are you using a single cable or an adapter + cable? I don't know what a higher quality cable is but at least you can try a different cable.

You could try running Windows to see if that clears it up. If it does, then you can try to figure out if it's using the same timing on the Mac. Maybe a program like PowerStrip can help figure that out. Or maybe there's a Windows driver info file for the display that can be examined (like the Mac's override file). If the timing is the same then that means there's some other difference in the AMD driver on the Mac side (voltage level? or whatever).

http://msdn.microsoft.com/en-us/library/windows/hardware/ff568432(v=vs.85).aspx

http://msdn.microsoft.com/en-us/library/windows/hardware/jj133967(v=vs.85).aspx

http://www.entechtaiwan.com/util/ps.shtm

Hey all...

Just got my nMP with 2 D700, already had the Samsung U28D590. When I noticed the glitch on the right side using it at 56 Hz (default operation mode from factory settings), it didn' t take long to find this tread, and after reading it thru got my display to work at 50 Hz, and I can tell you, that works MUCH better than with the HDMI cable at 30 Hz. I use this cable: Lenovo 0B47091 Mini-DisplayPort to DisplayPort Cable (you can find it from many sources).

I did as told on page 6, create the override file named DisplayProductID-b80 at /System/Library/Displays/Overrides/DisplayVendorID-4c2d/

Here's the step by step in case someone missed out (don' t type the " in the commands! 🙂):

1 - Go to Launchpad and start Terminal.

2 - type "sudo -s" and input your password.

3 - type "cd /System/Library/Displays/Overrides/DisplayVendorID-4c2d/".

4 - type "pico DisplayProductID-b80"

5 - copy and paste this inside:

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

<key>DisplayProductID</key>

<integer>2944</integer>

<key>DisplayVendorID</key>

<integer>19501</integer>

<key>IODisplayEDID</key>

<data>AP///////wBMLYALAAAAADQXAQS1PSN4Ol+xoldPoigPUFS/74BxT4EAgcCBgKnAswCVANEAq KwAoPBwM4AwIDUAX1khAAAaVl4AoKCgKVAwIDUAX1khAAAaAAAA/QAySx6GNgAKICAgICAgAAAA/ABVM jhENTkwCiAgICAgAXkCAwzwIwkHB4MBAAACOoAYcTgtQFgsRQBfWSEAAB4AAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAlw==</data>

</dict>

</plist>

Press Control + X, then y

6 - Reboot, or turn off and change the cable if you're using HDMI, and you're all set.

I tried the different frequencies joevt suggested, all gave me glitches...

Thanks a lot Joevt and others for the effort, I feel much better now that I can at least use my display and Mac Pro near optimum settings! That's great until a better solution arises...

Great summary dude, let us know if you get any of the horizontal glitches I mentioned... (didn't happen till a few days in for me)

Is there any summary like that available for those of us with the PB287Q? I sort-of understood the steps but not really since they were all spread out across multiple comments... :-(

I agree....

I've got everything just about set up.... I just can't figure out how to change the EDID file to be 50hz... I can manually do it, but it reverts back after a few minutes. The EDID is nearly twice as longs the Samsungs.

any help would be appreciated.

Laszlo

LaszloG wrote:

I agree....

I've got everything just about set up.... I just can't figure out how to change the EDID file to be 50hz... I can manually do it, but it reverts back after a few minutes. The EDID is nearly twice as longs the Samsungs.

any help would be appreciated.

Laszlo

How do you manually do it? What are you doing? What method do you think is the non-manual way? What reverts back after a few minutes?

The EDID of the ASUS monitor might have more info then Samsung's, but they both end up being 256 bytes, and you're only changing the preferred timing anyway so I don't so the problem there.

Anyway, I'll post an override for the ASUS later.

That would be great @joevt! Thanks!

hi Joevt,

First thing i did was change the displayport adapter to use 1.2 on the monitor itself.

i plugged in a miniDP to DP cable and lo0aunched SWitchResX v4.4..

I then selected the PB287Q, went to custom resolutions and change the vertical revolution to 50hz

I then save, reboot,and activate the custom resolution. i looks good, and gets activated, and is what I want, but a few minutes later k the screen goes dark, and the monitor reverts to either 30 or 60 hz It seems to happen when mouse hits a hot corner defined as putting the display to sleep

I was under the assumption that this workaround would always there until it is disabled.

when i run ioreg -w -0 -l | grep EDID ( I get to entries fior my two monitors...)

| | | | | | "IODisplayEDID" = <00ffffffffffff001e6ddb760101010132170104a55022789eca95a6554ea1260f505421080071 40818081c0a9c0b300d1c081000101e77c70a0d0a0295030203a00204f3100001a9d6770a0d0a022 5030203a00204f3100001a000000fd00383d1e5a20000a202020202020000000fc003334554d3935 0a202020202020015102031171230906074410040301830100009f3d70a0d0a0155030203a00204f 3100001a7e4800e0a0381f4040403a00204f31000018011d007251d01e206e285500204f3100001e 8c0ad08a20e02d10103e9600204f31000018023a801871382d40582c4500204f3100001e00000000 000000000000000000000000000000003a>

| | | | | | "IODisplayEDID" = <00ffffffffffff000469a2281ec4010010180104a53e22783a1cb5a3574fa0270d5054a30800d1 c0814081809500b30081c00101010150d000a0f0703e8030588a006d552100001a04740030f2705a 80b0588a006d552100001a000000fd001e5018a03c041100f0f838f03c000000fc00415355532050 423238370a202001f5020327714f0102031112130414051f900e0f1d1e23091707830100006a030c 00100000782000008c0ad08a20e02d10103e96006d5521000018011d007251d01e206e2855006d55 2100001e011d00bc52d01e20b82855406d552100001e8c0ad090204031200c4055006d5521000018 00000000000000000000000000000000eb>

The first one is from my LG34UM95, and the second one is from the ASUS PB287Q.

My questions revolve around how do i make the override file that gets placed in the /System/Library/Displays/Overrides folder.

Thanks in advance ,
Laszlo

I described the method I used to edid the EDID on page 7 (Jun 25, 2014 9:02 PM).

Lazlo, you have a PB287 model 28a2. The override file should be at /System/Library/Displays/Overrides/DisplayVendorID-469/DisplayProductID-28a2

The contents of an override file for product 28a2 that uses 3840 x 2160 50 Hz CVT-RB for the preferred timing mode should look like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>DisplayProductID</key>
  <integer>10402</integer>
  <key>DisplayVendorID</key>
  <integer>1129</integer>
  <key>IODisplayEDID</key>
  <data>AP///////wAEaaIoAAAAABAYAQSlPiJ4Ohy1o1dPoCcNUFSjCADRwIFAgYCVALMAgcABAQEBqKwAoPBwM4AwIDUAbVUhAAAaBHQAMPJwWoCwWIoAbVUhAAAaAAAA/QAeUBigPAQRAPD4OPA8AAAA/ABBU1VTIFBCMjg3CiAgATwCAydxTwECAxESEwQUBR+QDg8dHiMJFweDAQAAagMMABAAAHggAACMCtCKIOAtEBA+lgBtVSEAABgBHQByUdAeIG4oVQBtVSEAAB4BHQC8UtAeILgoVUBtVSEAAB6MCtCQIEAxIAxAVQBtVSEAABgAAAAAAAAAAAAAAAAAAAAA6w==</data>
</dict>
</plist>

For the PB287Q model 28a3, the override file should be at /System/Library/Displays/Overrides/DisplayVendorID-469/DisplayProductID-28a3

The contents of an override file for product 28a3 that uses 3840 x 2160 50 Hz CVT-RB for the preferred timing mode should look like this:

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>DisplayProductID</key>
  <integer>10403</integer>
  <key>DisplayVendorID</key>
  <integer>1129</integer>
  <key>IODisplayEDID</key>
  <data>AP///////wAEaaMoAAAAABQYAQSlPiJ4Ohy1o1dPoCcNUFS/7wDRwIFAgYCVALMAcU+BwAEBqKwAoPBwM4AwIDUAbVUhAAAaBHQAMPJwWoCwWIoAbVUhAAAaAAAA/QAeUBigPAQRAPD4OPA8AAAA/ABBU1VTIFBCMjg3UQogAUUCAydxTwECAxESEwQUBR+QDg8dHiMJFweDAQAAagMMABAAAHggAACMCtCKIOAtEBA+lgBtVSEAABgBHQByUdAeIG4oVQBtVSEAAB4BHQC8UtAeILgoVUBtVSEAAB6MCtCQIEAxIAxAVQBtVSEAABgAAAAAAAAAAAAAAAAAAAAA6w==</data>
</dict>
</plist>

I removed the serial numbers from the EDIDs.

Make sure the spaces or tabs are normal and not non-breaking spaces. Use plutil to make sure the files are valid. Make sure the vendor and product ids match your display.

I made a shell script to output the text of an override file given the path of an already edited EDID binary file:

#!/bin/bash
#
# Output the text for an override file
# $1: name of EDID file (128 or 256 bytes)
vendorid=$((0x$(dd if="$1" bs=2 skip=4 count=1 2> /dev/null | xxd -p)))
productid=$((0x$(dd if="$1" bs=2 skip=5 count=1 conv=swab 2> /dev/null | xxd -p)))
echo "Path: /System/Library/Displays/Overrides/DisplayVendorID-$(printf '%x' $vendorid)/DisplayProductID-$(printf '%x' $productid)"
echo '<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>DisplayProductID</key>
  <integer>'$productid'</integer>
  <key>DisplayVendorID</key>
  <integer>'$vendorid'</integer>
  <key>IODisplayEDID</key>
  <data>'$(base64 < "$1")'</data>
</dict>
</plist>'

Hey Laseyman,

Didn´t run into any so far, just one day using it though. I´ll keep you posted if they do show up...

Hello Joevt,

Still stuck at 56Hz after I attempted to use this file not sure whats going wrong. I am using Plist Edit pro. While the information is all inputting properly and i'm getting a total of 256 Hex Bits i can't get the content on to one line. I'm not sure if this is causing my problem or what? PLUTIL is showing an OK after running it.

Even though I have the PB287Q (at least according to what I bought and the specs), it's actually showing up as a PB287/28a2 from my Mac's perspective, so I used that file since the data in the file is the same.

I tried using the override file and it definitely did make a difference because when I rebooted the resolution options had changed (I was still connected via HDMI). I switched to DisplayPort and something wasn't set up right because the screen would display an image for about half a second, then go black, then about a second later display the image, then black, etc.

I'm going to try fooling around with the resolution switching utility to see if I can figure it out myself, but just wanted to give a quick update.

I was able to get it working at the native resolution at 50hz using the resolution switching utility. However, as others have noted working at a native 4K resolution makes things a bit too small for comfort, and there doesn't appear to be any way to create a scaled resolution using a custom "base" resolution. So at this point while it's nice to know that we can get it working at 50hz, until Apple enables that functionality themselves or fixes it to work at 60hz, we're pretty much stuck operating at 30hz for all "practical" purposes...

Kremmel, the name of the file should be DisplayProductID-28a2, not DisplayProductID-32a2. (Note: 32a3 is the ASUS PQ321 which is an older 4K MST monitor; I don't know what a 32a2 is).

I don't think the <data> contents needs to be on one line. It uses base64 encoding to encode the binary data. I think base64 will skip spaces, tabs, and newlines. If you want it on one line, then you can open the file in a text editor.

Orrbain, It's possible the PB287/28a2 and PB287Q/28a3 products might be the same monitor with different EDIDs. They have different preferred timings as I mentioned before, where the PB287 does not use a CVT-RB timing but the PB287Q does. If the PB287 does not like the 50 Hz CVT-RB timing but the PB287Q does, then it means their hardware (not just the EDID) is also different and we need a new EDID for the PB287.

As stated before, the reason why we're editing the EDID is to make a custom "base" resolution for scaled resolutions by editing the preferred timing. You can use SwitchResX to find a timing that makes your monitor work, but you have to use an override file to override the EDID to set the new timing as the "base" resolution.

So post your working timing and I'll post an EDID. If you can get a better timing in Windows, then post that too.

Here's a screenshot of the resolution that's working for me in the utility:

I also did the "Export EDID" thing in case that helps:

https://gist.github.com/rileydutton/9520d62b2cc70458616c