How to build your own iMac Pro [Successful Build/Extended Guide]

[joevt]

My post that was #11535 is now #11536 . Weird. Does that mean somewhere in the last 1154 pages of posts that a new post was added?

 

[kgp]

According to the manual for the 34WK95U-W, the Thunderbolt 3 port can be used as a USB-C input. This is a feature of displays that use the Titan Ridge Thunderbolt 3 controller. The USB-C port can be used with either a Thunderbolt 3 connection (e.g. MacBook Pro) or a USB-C with DisplayPort alt mode connection (e.g. MacBook). The manual is unclear whether this USB-C connection supports DisplayPort 1.4 (it says the max resolution for USB-C is 5120 x 2160 @ 60 Hz) or only DisplayPort 1.2 (it says the recommended resolution is 3440 x 1440 60 Hz).

The Moshi USB-C to DisplayPort cable is not a converter - The DisplayPort alt mode of USB-C directly uses the 4 pairs of wires of the USB-C cable as DisplayPort lanes. The cable is bidirectional so that it can be used as DisplayPort to USB-C. This could be used to connect the second PC via the DP1.4 port of its Vega.

Just ordered a Moshi USB-C to DisplayPort cable from Amazon. As soon it arrives on Monday I can do some tests.

Thanks for those. TB3 has two DisplayPort connections to your display, so there should be two EDIDs for TB3. Can you post both of them?

When two instead of one monitor are implemented for the LG 5K2K by OSX, SwitchResX can only export the EDID for the first monitor. For the second monitor there is not such option.

Thus I can offer now 4 SwitchResX EDID Exports:

1.) LG 5K2K via DP1.4 port of GC-Titan Ridge: LG HDR 5K Titan Ridge DP1.4(OK).txt. Correct 1x monitor implementation of the LG 5K2K @5120x2160 pix resolution without any custom resolution profile.

2.) LG 5K2K via TB3 port of the GC-TitanRidge without defining custom resolution profile:LG HDR 5K Titan Ridge TB3 (2 Displays).txt.zip. Incorrect 2x monitor implementation of the LG 5K2K @ max 3680x2160 pix (Display 1) and max 2560x2160 pix (Display 2) resolution.

3.) LG 5K2K via TB3 port of the GC-TitanRidge with a custom resolution profile: LG HDR TB 5K 2monitor .txt.zip. Incorrect 2x monitor implementation of the LG 5K2K @ 5120x2160 pix (Display 1) and 5120x2160 pix (Display 2) resolution. However only one screen with 5120x2160 is displayed on the LG 5K2K. Permanent switch between 1 und 2 Monitor implementation apparent in the SwitchResX GUI. During changes between 1x and 2x display OSX implementation of the LG 5K2K, black screen.

4.) LG 38UC99 via DP1.4 of the GC-Titan Ridge (3860x1600 pix) and LG 5K2K via TB3 port of the GC-TitanRidge with a custom resolution profile: LG HDR 5K-TB3-OK.txt.zip. Correct 1x monitor implementation of the LG 5K2K @5120x2160 pix resolution in the SwitchResX GUI.

What custom EDID? Did I miss a post? Or do you mean the custom resolution from your screenshot? Custom resolutions are separate from custom EDID. Both are stored in the files at /System/Library/Displays/Contents/Resources/Overrides

You can see how the changes you make in SwitchResX are stored by looking at those files.

I previously referred to the custom resolution apparent in my screenshot. In case of 3.) and 4.) above I also disabled postiv. sync in the custom resolution settings, which seems to display only one instead of two TB screens on the LG 5K2K with 5120x2160 TB screen resolution.

What would be the DisplaVendorID of the LG5K2K to be found under /System/Library/Displays/Contents/Resources/Overrides?

 

[kgp]

DisplayID is a standard. Where do you get Display ID 1.1 or 1.2 from? Are you referring to the EXTENSION EDID BLOCK -> DID-EXT: Display ID Extension -> DisplayID version?

The manual for the LG 5K2K has a list of resolutions. It says 5120 x 2160 60 Hz has positive horizontal sync and negative vertical sync. Are you saying that doesn't work and both should be negative?

Also, my post #11535 is awaiting moderator approval (I don't know why), so watch for that.

Yes and yes. Seems that when connected via TB3 of the GC Titan Ridge with Displayport setting DP1.4 on the LG 5K2K, both positiv horizontal and vertical syncs should remain unchecked to enable 5k2k resolution.

Edit: With positive sync. enabled, the LG 5K2K shows sync issues when connected via the TB3 port of the GC-Titan Ridge

Anyway, the important thing seems the use of a custom resolution profile, which enforces 5120x2160 pix resolution @59,990 Hz when connecting the LG 5K2K via the TB3 port of the GC-Titan Ridge. The remaining problem is the two monitor entry in the SwitchResX Gui, when only connecting the LG 5K2K via Tb3 of the GC-Titan Ridge.

A general problem though is that after switching off the system, during the subsequent boot all settings are lost and one just boots into a black screen, while a simple reboot keeps the actual Lg 5K2K / GC-Titan Ridge configuration and also properly shows Boot screen and Clover boot menu with the LG 5K2K connected to the TB3 of the GC-Titan Ridge.

 

[RuleBreaker01]

For instance was also a question ..
Can you provide a proposal for a custom edid that could work with the 5k2k? @flymovies could you dump an edid with switchresx that works with your macbook pro 15 (2018) and the 5k2k via TB?

I can't propose anything as I don't believe you will achieve what you want to do with custom EDID.

It's obvious to.me that the LG is limited to DP 1.2 over TB3, so it can't do native resolution. Hence why the two screens. The issue is similar to what the original Dell 5k screen had. Then when the Dell worked, the HP didn't until Apple added support for that screen.

IIRC, for a while to get the HP z27q working you had to patch a kext so that the two panels were seen as one. Maybe that same fix will work for this LG. Worth trying.

 

[kgp]

I can't propose anything as I don't believe you will achieve what you want to do with custom EDID.

It's obvious to.me that the LG is limited to DP 1.2 over TB3, so it can't do native resolution. Hence why the two screens. The issue is similar to what the original Dell 5k screen had. Then when the Dell worked, the HP didn't until Apple added support for that screen.

IIRC, for a while to get the HP z27q working you had to patch a kext so that the two panels were seen as one. Maybe that same fix will work for this LG. Worth trying.

The custom EDID was your idea and in fact it works partly, ESPECIALLY with the GC-Titan Ridge!

The TB part of the monitor btw is neither compatible with the Titan Ridge nor with the Alpine Ridge and only works after heavy patching until you switch of the PC and all is lost when booting the system (black screen already at early boot during splash screen, clover boot manager and verbose boot messages). It is not only an issue with macOS, but a general Titan Ridge and Alpine Ridge initialisation incompatibilty already during very initial system boot.

One should only aim for the LG 5K2K with the clear aim to use it and it’s 5K2K resolution via DP1.4, which works absolutley flawless. TB on this monitor for now is just a incompatible and largely useless gimmic. On monday I will try if one can at least use the monitor also via USB-C with a bidirectional USB-C to DP1.4 cable. This might be the only way to connect the LG 5k2k with two PCs.

After this last testing I will return the monitor to Amazon. Nothing I would seriously purchase for myself at roughly 1300€.

 

[RuleBreaker01]

The custom EDID was your idea and in fact it works partly, ESPECIALLY with the GC-Titan Ridge!

I think that you're confusing me with someone else.

 

[RiLinux]

PRIME X299-DELUXE BIOS 1603
Update RC version to 1.1.5.
Improved system performance and stability.
Updated iRST and RSTe.
Fixed some device compatible issues. (peripheral, storage, fan, external USB card).
Using USB BIOS Flashback, please rename to “X299D.CAP" after download

 

[joevt]

Just ordered a Moshi USB-C to DisplayPort cable from Amazon. As soon it arrives on Monday I can do some tests.

I hope it works out. There are a couple questions about USB support that are not clear in the manual. It seems there are three methods for USB support.
1) Thunderbolt USB controller. You showed this in your screenshot. The Thunderbolt USB controller of the display has two ports but only one seems to be used - it has a USB 3.0 hub connected internally where one port is used for the USB controls of the display (brightness control, etc.). Audio is only through DisplayPort or HDMI (LG UltraFine used USB audio). Devices can use USB 3.0 speed?

2) USB 2.0 USB-B input. The USB controller of your computer is used. Devices are limited to USB 2.0 speed.

3) USB-C input (via the Thunderbolt port for computers that don't have Thunderbolt). The USB controller of your computer is used. This supports USB 3.0 speed? If so then 5K2K 60Hz cannot be supported. So you will have to change the display option to get USB from the USB-B port. Hopefully the monitor is smart enough to allow 5K2K 60Hz over USB-C by not forcing USB 3.0 support. It would be better if the monitor supported switching the USB-C input between USB 2.0 and USB 3.0 speed so that only one cable would be required for USB and DisplayPort signals.

When two instead of one monitor are implemented for the LG 5K2K by OSX, SwitchResX can only export the EDID for the first monitor. For the second monitor there is not such option.

Very strange. It might be useful to create a program to read DDC directly, since it is unclear if SwitchResX is returning an unmodified EDID. There are some DDC programs for macOS to control options like brightness that could be easily modified to read both the EDID and DisplayID I2C addresses of DDC.

I think moninfo.exe (Monitor Asset Manager) in Windows uses DDC to read directly EDID.

Thus I can offer now 4 SwitchResX EDID Exports:

1.) LG 5K2K via DP1.4 port of GC-Titan Ridge: LG HDR 5K Titan Ridge DP1.4(OK).txt. Correct 1x monitor implementation of the LG 5K2K @5120x2160 pix resolution without any custom resolution profile.

2.) LG 5K2K via TB3 port of the GC-TitanRidge without defining custom resolution profile:LG HDR 5K Titan Ridge TB3 (2 Displays).txt.zip. Incorrect 2x monitor implementation of the LG 5K2K @ max 3680x2160 pix (Display 1) and max 2560x2160 pix (Display 2) resolution.

3.) LG 5K2K via TB3 port of the GC-TitanRidge with a custom resolution profile: LG HDR TB 5K 2monitor .txt.zip. Incorrect 2x monitor implementation of the LG 5K2K @ 5120x2160 pix (Display 1) and 5120x2160 pix (Display 2) resolution. However only one screen with 5120x2160 is displayed on the LG 5K2K. Permanent switch between 1 und 2 Monitor implementation apparent in the SwitchResX GUI. During changes between 1x and 2x display OSX implementation of the LG 5K2K, black screen.

4.) LG 38UC99 via DP1.4 of the GC-Titan Ridge (3860x1600 pix) and LG 5K2K via TB3 port of the GC-TitanRidge with a custom resolution profile: LG HDR 5K-TB3-OK.txt.zip. Correct 1x monitor implementation of the LG 5K2K @5120x2160 pix resolution in the SwitchResX GUI.

#3 and #4 are the same. Added custom resolutions does not create a custom EDID. Custom resolutions are stored separately from EDID in the Overrides files.

#1 has a mode for 5120 × 2160 @ 60.000Hz but #2 has only a mode for 2560 × 2160 @ 59.662Hz

#3/#4 are identical to #2 but have an extra Display ID extension block (version 1.1 where the rest are 1.2) containing the missing "5120 × 2160 @ 59.990Hz" resolution.

Maybe an error occurs in the case of #2 while reading the extra extension blocks from DDC. That doesn't make sense since #2 contains the proper extension block count at byte 7E of the first block.

I wonder if #3/#4 is the EDID to support DisplayPort 1.4 SST and #2 is the EDID to support DisplayPort 1.2 Dual Link SST.

I would like confirmation that this display can support 5K2K 60Hz from a Mac using Alpine Ridge (therefore using DisplayPort 1.2 Dual Link SST).

If the display is working as DisplayPort 1.4 700 MHz via Titan Ridge, then you should be able to disconnect one of the DisplayPort cables from the GC-TITAN RIDGE or connect it to a different graphics card.

I previously referred to the custom resolution apparent in my screenshot. In case of 3.) and 4.) above I also disabled postiv. sync in the custom resolution settings, which seems to display only one instead of two TB screens on the LG 5K2K with 5120x2160 TB screen resolution.

Interesting. We don't know exactly how Thunderbolt transforms DisplayPort signals.

What would be the DisplaVendorID of the LG5K2K to be found under /System/Library/Displays/Contents/Resources/Overrides?

Vendor = Manufacturer, so you need to look in the "DisplayVendorID-1e6d" folder. You can make a change in SwitchResX, save it, and view the files by Date Modified. There's an interesting file in there for the Thunderbolt port of this display (Product ID 7721; The DisplayPort has Product ID 7720). The DisplayProductID-7721.mtdd file describes the multi cable connection information for the display. The overlay data appears to be an EDID but it's different than the three you provided.

 

[Attila]

I created a Mojave USB installer; I get to the installer screen, but am having keyboard issues --- as I try to enter the disk name in DiskUtility, the keystrokes lag really bad. e.g. I type a "F", and a few seconds later two Fs are displayed.

Any ideas what the problem might be?

 

[cloverbay]

Hi guys, I bought a Sapphire Vega64 card on Black Fri. After I swap out the old nvidia GTX970, I can no longer boot into H.Sierra. I understand this is not exactly a drop in replacement, so does anyone knows what settings I have to change?

After this line loaded, the screen will be blank and the computer sounds like it's been shut off, very quiet and not proceed further.

Thank you guys in advance.