Mac Pro Late 2013 and Samsung 4k monitor problem

Good news! I have this same issue running 10.9.5. But I installed the golden master (build 14A379b) of Yosemite tonight and my Samsung displays perfectly @60hz at all resolutions! FINALLY! Yosemite should be out in just a few more days so rest easy Samsung U28D590D owners! Relief is on the way!

I have 2x MacPro 6,1 and a Samsung U28D590

MacPro 6,1: 3.7 GHz Quad-Core Intel Xeon E5, AMD FirePro D300 2048 MB

MacPro 6,1: 3.5 GHz 6-Core Intel Xeon E5, AMD FirePro D700 6144 MB

Running 10.9.5 on both MacPro, the D300 worked fine at all resolutions when using MDP-DP cable

System profile correctly showed 3840x2160@60Hz

The D700 did not - and had lots of tearing and distortion down the right side of the screen using the same MDP-DP cable

(System profile correctly showed 3840x2160@60Hz)

(HDMI cable worked ok at 30Hx for both too...)

However:

After updating to Yosemite 10.10.1 both systems worked fine with no distortion at all resolutions at 60Hz using a MDP-DP cable.

I used an external Thunderbolt drives to test systems before committing to update - so I updated a 10.9.5 external Thunderbolt drive to 10.10.1

The Boot ROM Version of the MacPro with D300 has been updated from MP61.0116.B04 to MP61.0116.B07 but nothing else seems to have changed

Using the 10.10.1 Thunderbolt drive, the MacPro with the D300 worked fine as before.

Then connecting the 10.10.1 Thunderbolt drive to the MacPro with the D700 it also worked fine - without any other updates...

So without any firmware updates, it seems that Yosemite has fixed the issue with both of my MacPro.

(not tried a MacPro with a D500 - so cannot comment there)

Shame about the design of Yosemite OS - don't like the new looks...

S

Poyda wrote:

I sent the developer of SwitchResX an email asking if it was possible, here is the reply:

You cannot define which resolution is used as a basis for the scaled resolutions. Scaled resolutions are all "children" of a master resolution, which is always the same, and which is chosen by MacOS X - this is not a choice that can be influenced by SRX

Moreover, as far as I know, Apple has decided that AMD display drivers cannot use scaled resolutions apart those that are stored in a hardcoded list in their display driver. I may be wrong, but this simply means that you cannot get any HiDPI resolution that is not "apple-approved" on a MacPro.

regards

Stephane

I know that Mountain Lion was the last version I was able to create scaled resolutions that are greater in size than the native display size for the Radeon HD 5870 (for HiDPI testing). Apple removed the feature for no good reason. I don't know if Apple has changed that since then because I use an NVIDIA GTX 680 now. It seems that OS X drivers for NVIDIA and AMD are developed separately and don't maintain feature parity.

But Poyda said he was able to create the scaled resolutions that he wanted - they were just using the native timing of the display instead of the new 50 Hz timing. So to solve this, you have to figure out how to make the driver think that 50 Hz is the native timing of the display. The only way I can think to do that is to override the EDID of the display. It may or may not work though.

To override the EDID for the U28D590D you need to create an override file at /System/Library/Displays/Overrides/DisplayVendorID-4c2d/DisplayProductID-b80

Here's a version of an override file for the U28D590D with the preferred timing set to 50 Hz:

<?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/74BxT4EAgcCBgKnAswCVANEAqKwAoPBwPoAwIDUAX1khAAAaVl4AoKCgKVAwIDUAX1khAAAaAAAA/QAySx6GNgAKICAgICAgAAAA/ABVMjhENTkwCiAgICAgAW4CAwzwIwkHB4MBAAACOoAYcTgtQFgsRQBfWSEAAB4AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAlw==</data>
</dict>
</plist>

Have you tried refresh rates higher than 50 Hz? 56 Hz is the highest before the pixel clock exceeds 500 MHz which might be a possible limit of the driver. Here's the same override with the preferred timing set to 56 Hz.

<?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/74BxT4EAgcCBgKnAswCVANEAC8IAoPBwPoAwIDUAX1khAAAaVl4AoKCgKVAwIDUAX1khAAAaAAAA/QAySx6GNgAKICAgICAgAAAA/ABVMjhENTkwCiAgICAgAfUCAwzwIwkHB4MBAAACOoAYcTgtQFgsRQBfWSEAAB4AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAlw==</data>
</dict>
</plist>

The EDID of the U28D590D says the minimum vertical refresh is 56 Hz so I am not sure why the driver would ignore that and allow your custom 50 Hz timing but since you got it to work, I've updated the EDID to show 50 Hz as the minimum refresh.

If you used SwitchResX to create an override then there might be a file named DisplayYearManufacture-2013-DisplayWeekManufacture-52. Just check the DisplayProductID and DisplayVendorID inside the file to be sure or you could use the "Restore factory settings" option in SwitchResX first before creating the DisplayProductID-b80 file. I'm guessing the Year/Week file created by SwitchResX takes precedence over the ProductID file or SwitchResX removes the ProductID file.

Did you restart the computer?

Make sure no other files exist in the DisplayVendorID-4c2d folder (unless they have a different ProductID).

Make sure Finder preferences has "Show all filename extensions" selected and verify the file has no extension.

Make sure the format of the file is correct by right clicking it and selecting "Open in Property List Editor.app". Or you can type the following command in Terminal.app (it should say OK):

plutil /System/Library/Displays/Overrides/DisplayVendorID-4c2d/DisplayProductID-b80

You could verify the folder path is correct by using SwitchResX to create a timed resolution, type Command-S to save the timed resolution, and check that a file with the modification date of now exists in the DisplayVendorID-4c2d folder. Replace the file with the one you created and restart.

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...

PB_NB wrote:

Hi joevt,

Is it possible to make a data line for the override file that is actually 60 Hz. for the Samsung 4k monitor? I have been using the 50 Hz file for a while and it has been much better than the 56 Hz which causes the picture overlap on the right hand side but still a little lagging. 57 Hz also causes the same overlap but it appears to be thinner to the edge. The monitor seems to be okay going past 57 Hz and so does the nMP (D500 model). I have just switched over to the 54 Hz. now and the picture is getting better all the time.

Thanks,

PB

There's no way to know unless you find a mode that works or you find that all possible (at least reasonable) modes don't work. You can use SwitchResX to try different modes. I guess you would want to play with the horizontal blanking values. The horizontal blanking period consists of 3 parts: the front porch, the sync pulse, and the back porch. For CVT-RB timings, it looks like this (16 pixels per character):

–––__––––– (48 front porch, 32 sync width, 80 back porch)

You can move the sync pulse left or right (make a change in the front porch and the opposite change in the back porch) which would have the affect of moving the display left or right on a CRT (not sure what the result would be on an LCD).

You can change the width of the sync pulse (make a change in the sync pulse and the opposite change in the front or back porch).

You can make the total blanking period shorter or longer, but then you would need to adjust the pixel clock to keep the vertical refresh rate at 60 Hz (which means a line will take the same amount of time, but the blanking will be a different fraction of the time).

If the display works in Boot Camp on the same Mac, then you could get the data line from that and use it in Mac OS X. If the data line is the same then it means the Mac OS X driver has some other problem.

Hi,

I just installed OSX 10.10 DP4 a moment ago. And this issue seems to have been fixed. I'm using Dual D500 version Mac Pro 2013 and Samsung U28D590D display, with a normal/unnamed Mini DP to DP cable.

Here's the picture taken from iPhone:

Just incase it this info helps anyone - I have a D300 6 core nMP and could only get very low resolution content to work on Samsung over Display Port. I was using a Deltaco branded 1.2 DisplayPort cable (the only type I could get in Sweden). I swapped it out for a "Clicktronic" branded cable from Amazon Germany and now I'm running at 60Hz in 4K glory! The info on the DisplayPort website about all 1.2 spec cables being the same is BS!

Also as other posters have noted - there's no tearing on the right hand side of the screen in 10.9.4 on the D300.

kim.bjoern wrote:

Many thanks for your time joevt. I did have this info - but should have asked more precisely:

I've been using some of the other override files shown in this discussion, and I have the structure and file-name correct.

/System/Library/Displays/Overrides/DisplayVendorID-410c/DisplayProductID-8d7

I was asking for the correct data (integer?) in the override file, as it currently displays the Samsung info.

<key>DisplayProductID</key>

<integer>2944</integer>

<key>DisplayVendorID</key>

<integer>19501</integer>

Thanks again - Kim

If you got it to show the Samsung name, then you got everything to work. I guess the graphics driver ignores the incorrect integer values that you have in the override file. The name is another part of the EDID independent of the vendor and product ID. Since you're using the Samsung EDID, you have to change the EDID to show the Philips name (you should probably use an EDID editor to do that - so that it recalculates the checksum too). Or you could start with the original Philips EDID and just change the preferred timing (again, using an EDID editor). Here I changed the pixel clock to 444.50 MHz to give a refresh rate of 50.011 Hz:

<?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>2263</integer>
  <key>DisplayVendorID</key>
  <integer>16652</integer>
  <key>IODisplayEDID</key>
  <data>AP///////wBBDNcIAAAAABAYAQSlPiJ4OlUloVdPoCgPUFS9SwDRwIGAgUCVD5UAswCBwAEBoq0AoPBwPoAwWIoAbVUhAAAaAjqAGHE4LUBYLEUAbVUhAAAeAAAA/ABQaGlsaXBzIDI4OFA2AAAA/QAXUB6gPAEKICAgICAgARkCAyP0SwECAwQFkBESExQfIwkHB4MBAABqAwwAMAAAeCAAAAI6gNByOC1AECyWgG1VIQAAGAI6gBhxOC1AWCyWAG1VIQAAGAR0ADDycFqAsFiKAG1VIQAAGgEdALxS0B4guChVQG1VIQAAHgAAAAAAAAAAAAAAAAAAAAAAAAAAgA==</data>
</dict>
</plist>

The Phillips display uses longer pulse widths than what SwitchResX calculates using CVT-RB but the blanking periods are the same so I didn't change them for 50 Hz.

http://support.apple.com/kb/ht6008

Using 4K displays and Ultra HD TVs with Mac computers

says

You can use 4K displays and Ultra HD TVs with your MacBook Pro (Retina, Late 2013 and later), Mac Pro (Late 2013), and iMac (27-inch, Late 2013) computer. You can use these displays at the following resolutions and refresh rates with the built-in HDMI port.

• 3840 x 2160 at 30 Hz refresh rate
• 4096 x 2160 at 24 Hz refresh rate (mirroring is not supported at this resolution)

With OS X Mavericks v10.9.3 or later, the following DisplayPort displays are supported at their default usingsingle-stream transport (SST) at 30Hz.

• Sharp PN-K321
• ASUS PQ321Q
• Dell UP2414Q
• Dell UP3214Q
• Panasonic TC-L65WT600

MacBook Pro (Retina, 15-inch, Late 2013) or Mac Pro (Late 2013) also support multi-stream transport (MST) displays at 60 Hz . These displays need to be manually configured to use MST. Follow the steps below to use the display's built-in controls to enable this feature.

• Sharp PN-K321: Choose Menu > Setup > DisplayPort STREAM > MST > SET
• ASUS PQ321Q: Choose OSD menu > Setup > DisplayPort Stream
• Dell UP2414Q and UP3214Q: Choose Menu > Display Setting > DisplayPort 1.2 > Enable
• Panasonic TC-L65WT600: Choose Menu > Display Port Settings > Stream Setting > Auto

Your Mac will automatically detect an MST-enabled display. However, your display may require a firmware update to support 60Hz operation. Please contact your display vendor for details. If your specific DisplayPort display is not listed above, check with the display’s manufacturer for compatibility information.

If the "tearing issue" that you're speaking of is the distortion on the right side of the screen, I found that both the beta, and now the official release of Yosemite has fixed the issue. I no longer have that annoying distortion on the right hand side of the screen. To confirm, I am using a Samsung U28D590D running Yosemite 10.10 Rev. 14A389

No guarantees on any of this - I can only report my own findings...

I used an external Thunderbolt drive with 10.10.1 to test my MacPro 6,1 systems before committing to updating it 10.9.5

I used SuperDuper to disk image and clone the MacPro internal HD on to an external Thunderbolt HD, then updated the external Thunderbolt HD to Yosemite.

Might be worth you trying to install 10.10.1 on an external Thunderbolt drive to test first...

It solved my problems with the Samsung U28D590 on the MacPro with D700

Shame about the design of Yosemite OS - don't like the new looks...

S

Apple has updated the 4k display support page.

http://support.apple.com/kb/HT6008

It clearly state Mac OS X 10.9.3 only support Single stream Transport (SST) at only 30Hz. SST is what Samsung monitor used.

It also state with list of monitors that support Multiple stream transport (MST), 60HZ can be used and supported.

I guess 4K monitor support is much more complicated than I originally thought.

The EDID of the Samsung monitor was posted on MacRumors. It does mention that it supports a 2560 x 1440 mode with the same parameters I listed. It also has a timing for 1920 x 1080 as well as the native 3840 x 2160.

It also lists frequency ranges which suggests it has a scalar that can support custom resolutions not listed here. In that case, you might try creating different resolutions and/or frequencies to find what limit (resolution or pixel clock or refresh rate) is causing the problem. Maybe it's an HBR2 problem? At what frequency does DisplayPort 1.2 switch from HBR to HBR2?

For resolutions: If 2560 x 1440 at 60 Hz works without problem, then you can try creating larger resolutions at 60Hz by adding multiples of 32 to the horizontal and 18 to the vertical (to keep the 16:9 ratio) up to 3840 x 2160. The reason to use 32:18 is because some drivers don't like odd number of vertical lines. You could try going beyond 3840 x 2160 to test if the monitor scalar can shrink the input. We already know that the graphics card scalar can shrink the output to support larger HiDPI modes.

For frequencies: If 2560 x 1440 at 60 Hz works without problem, then you could add other 2560 x 1440 timings by adding multiples of 5 Hz to the refresh rate up to the point where the pixel clock is 540 MHz or the refresh rate is 75 Hz.

Detailed mode: Clock 533.250 MHz, 607 mm x 345 mm

3840 3888 3920 4000 hborder 0

2160 2163 2168 2222 vborder 0

+hsync -vsync

Detailed mode: Clock 241.500 MHz, 607 mm x 345 mm

2560 2608 2640 2720 hborder 0

1440 1443 1448 1481 vborder 0

+hsync -vsync

Detailed mode: Clock 148.500 MHz, 607 mm x 345 mm

1920 2008 2052 2200 hborder 0

1080 1084 1089 1125 vborder 0

+hsync +vsync

Monitor ranges (GTF): 56-75Hz V, 30-134kHz H, max dotclock 540MHz

I had a similar problem with MacPro4,1 and a AMD7950 on the Samsung 4k. I did discover that dropping the refresh rate to 50Hz would result in no artifacts. 55Hz still gave some, but less. My understanding is the nMP is using the same drivers, so the same fix might work if you're willing to live with a slight refresh drop. I used SwitchResX to make the mode, though I'm sure there's other ways.

My bigger problem was the system would not boot with the monitor attached to the 7950's displayport, so I swapped to a GTX 680 which works fine (as others noted)