DIY 5k Monitor - success :-)

[PaulD-UK]

@Mowgli10L
Yes, as in the diagram for the Control Strip power button.
But the 6mm Tactile switch buttons are available on eBay or Amazon everywhere, so don't bother with desoldering anything or resoldering wires differently, just make a new button strip in a new shape.

 

[Mowgli10L]

@Mowgli10L
Yes, as in the diagram for the Control Strip power button.
But the 6mm Tactile switch buttons are available on eBay or Amazon everywhere, so don't bother with desoldering anything or resoldering wires differently, just make a new button strip in a new shape.

Thnx a million!

 

[shijan]

I guess t could be somehow simpler and prettier just cut the cable and attach larger sized buttons mounted directly to holes drilled into iMac body.

 

[paulpijnenborg]

Hi All,
First: thanks to the founders and posters on this forum.
second: there is a lot to read so I may missed some things, sorry if asked/answered earlier.

1. my iMac 27 2017 broke down and they cannot pinpoint the problem.
2. planning using the JRY-W9RQUHD-SA1 board and LRS 250-24v
3. Original USB A ports: I did not read of any one using these. Why? Was thinking, as my boards are broken, to just cut of that part (keeping the fixing holes) and solder the wires of a splitter cable to the USB A ports. Will this work? Will the SA1 board deliver enough power?
4. The SD reader: can I transform it with soldering a cable to an USB A connector. There will be an USB Hub inside!
5. Ethernet port: See 4. AIWI did such a project but replaced parts.
6. HDMI, DP and USB C: There are various adaptors (like AIWI uses in his project) I would modify the original holder, remove, cut etc. so I can fit in the adaptors. Using/remodeling 1 USB A port to HDMI. (USB c soldering is to complicated)
7. Headphone: Can the original cable (goes al the way to the other side of the iMac if correct) not be soldered to the headphone of the SA1 board?
8. Speakers: that I understand, but still wonder if an extra amplifier is needed.
9. Webcam and Microphone: clear for me.
10. Power button: clear for me
11. OSD board: thinking of putting new (extra) buttons on the RAM door. Not very accessible but you would not need them much.

I understand all is a big project and I may get over my head. if things are broken I like to repair them but no super tiny solder work.
So, thanks again and all info is welkom, especially the solder points regarding the original board.

Paul

 

[PaulD-UK]

@paulpijnenborg "I understand all is a big project and I may get over my head."

Hi. I recommend not being too over-ambitious at first... 😅

"3. Original USB A ports: I did not read of anyone using these."
@Aiwi in his blog (link) has shown how the USB-A ports can be used.

But the thing to bear in mind is that the USB-C cable between a Mac and a 5K monitor doesn't have enough bandwidth to carry video AND USB 3.0 signals.
The JRY--SA1 has a USB-B input port on it that needs a separate USB connection from the Mac to use the two USB-A ports on the board at USB 3.x speed.

So unless you are going to run two USB cables from the Mac to the monitor, you can only expect to get USB 2 from any USB-A ports on your monitor. Only good enough for keyboard and mouse...

"4 The SD reader: & 5 Ethernet port:"
This also is going to require more bandwidth than is available from a single cable, unless you do some clever USB 3.x cabling.

"6 HDMI, DP and USB C:"
The video cable to a 5K monitor is very high frequency and bandwidth.
Any extension cables you use MUST be of the highest 8K quality.
Short DP 1.4 and USB-C 8K extension cables can be found, and work OK - especially if you are only a short cable between the Mac and the monitor's extension cable.
Short HDMI 2.1 8K extensions don't seem to be sold, so any HDMI 2.0 extension cable will only give 4K.

With a desktop setting, where a longer video cable (over 0.8 metres) is needed, then only the highest quality extension cables are recommended, or the video signal could become affected by signal loss or static electricity.

"7 Headphone: Can the original cable (goes all the way to the other side of the iMac if correct) not be soldered to the headphone of the SA1 board?"
Apple use a micro ribbon cable to internally connect the 3.5" audio input to the logic board. This can have a soldered extension, but it's difficult and tiny.

"8. Speakers: that I understand, but still wonder if an extra amplifier is needed."
The JRY--SA1 board only has a 3 watt amplifier, which is useable, but not as good as the better 10 watt amplifier in the R1811 board.

"11. OSD board: thinking of putting new (extra) buttons on the RAM door."
Mounting the Control Strip is one of the major problems to be sorted out when planning your monitor conversion.
Some people have built their own control strip with new buttons in a different configuration, or using a small 5-way joystick.
It's best to check previous posts in this thread, and choose how you want to do it.

It's best to allow good access, as you will need to adjust the OSD...

 

[paulpijnenborg]

Hi Paul
Thanks for the quick answer and tips. yes I know that I am over ambitious probably.

3) "But the thing to bear in mind is that the USB-C cable between a Mac and a 5K monitor doesn't have enough bandwidth to carry video AND USB 3.0 signals.
The JRY--SA1 has a USB-B input port on it that needs a separate USB connection from the Mac to use the two USB-A ports on the board at USB 3.x speed."
??? you lost me here... not enough bandwidth? saying that if I connect an external HDD to the monitor the Mac cannot handle/see the HDD and video?
Must I see it this way:
the USB C (surely not usb4) port of the SA1 is only for video and I must find a way (separate cable) to connect Mac to the monitor ports, cam mic usb port etc?
Regard the SA1, the usb ports of it.... do I understand it correctly that the USB B port is for the power of the 2 USB A ports? Forgive my simple mind. I thought the SA1 board was powering these ports? why would they place USB ports if they are not "useable".
These usb 3.0 was a plus to choose the SA1!

4, 5 and 7 are indeed more expert projects. I need to see how all is in live vision. The iMac is closed, so I am brainstorming with photos and details.

8 it has to do. only an occasion meeting (which we use headphones)
11 hmmm already looking half a day to the iMac where to place them. The Ram door for now seems the most logical place. Looking at my TV the button are also in hidden in back, side or under

Thanks, I need further study of this.

 

[PaulD-UK]

@paulpijnenborg
Any USB-3 hub connected to a Mac and with SSDs connected to the hub can only run a monitor at 4K 30Hz !!!

Modern GPUs can manage 60Hz but not at 5K.

It has to be a Thunderbolt 3 hub/dock to do 4K 60Hz (at the same time as SSDs), and TB 4(or 5) to do 5K 60Hz.
The Apple Studio Display or the LG 5K Ultrafine monitors are Thunderbolt 3, so can have USB 3.0 ports on the monitor with just one TB 3 cable.

All the video conversion boards to make iMac 5K monitors are only USB-C, and 5K video takes all the USB-3.x channels in the actual USB-C cable to carry the video.

USB 2 signals are carried on separate wires, so that is why there can be USB-A (USB 2) output ports on the board.
The reason they do this is to give the basis of a KVM switch inside the monitor, but only at USB 2...

The JRY--SA1 board has a USB-B input port to connect to the computer to provide USB 3.x outputs through it's USB-A monitor ports.

That's just the way it is... 😶

 

[obesechess]

@obesechess "Anything I need to make it work other than a R1811 V4 control board, an appropriate power supply, and a Thunderbolt cable? Do I need a separate backlight control board, or does the v4 handle that well enough?"

The 2015 iMac's LM270QQ1 SD(B1) screen can develop 'pink edges' with age, and it only supports ~91% Display P3, and since you don't intend to use the iMac's speakers, you could get good results with the cheaper JRY-W9RQUHD-SA1 board as an alternative to the R1811 V4.

The major thing you would lose is an I/R remote control.
And a lower spec audio amplifier, which won't be a concern for you

However if you intend to use the HDMI input for 5K, with the HDMI 2.1 version of the R1811, then that is the one to go for.
The other advantage of the R1811 HDMI 2.1 version is that it comes with better firmware, which gives more info about the board's operational parameters.

For ordinary use you won't need the extra DZ-LP0818 backlight control board with the R1811, as the board's internal backlight circuit is fine for everything but use of the screen in constant direct sun on the glass.

You don't need a TB3/4 cable, as an 8K video-capable USB-C cable is OK.
But it may be easier to go with a TB/4 cable as that guarantees good video performance.

Good luck with the conversion. 😉

Will the JRY-W9RQUHD-SA1 give me the same video results as the R1811 V4?

If so, then I would just need the JRY-W9RQUHD-SA1, a DZ-LP0818 and a TB3/4 or 8K USB-C cable?

I don't need the I/R remote or an audio amplifier - I've never needed a remote on my current monitor, and all of my audio stuff is handled by outboard equipment.

Thank you!

 

[joevt]

Any USB-3 hub connected to a Mac and with SSDs connected to the hub can only run a monitor at 4K 30Hz !!!

Modern GPUs can manage 60Hz but not at 5K.

Same applies with or without SSDs connected.
4K60 8bpc RGB should be possible with HBR3 x2 without DSC.
5K60 with DSC or 8bpc 4:2:0 should also be possible with HBR3 x2.

The problem is that 5K displays might not accept DSC and/or HBR3.

A DisplayPort 1.4 MST hub can convert HBR3 x2 to HBR2 x4 or HBR3 x4 with DSC decompression or DSC pass thru.

DSC decompression doesn't support 10bpc in most or all? DisplayPort 1.4 MST hubs, but that's ok because HBR3 x4 without DSC cannot do more than 5K60 RGB 8bpc anyway.

So the USB-C hub that supports USB3 needs to include a DisplayPort 1.4 MST hub (The CalDigit SOHO is one such USB-C hub) or a separate MST hub needs to be attached.

All the video conversion boards to make iMac 5K monitors are only USB-C, and 5K video takes all the USB-3.x channels in the actual USB-C cable to carry the video.

Do any of the display boards with a USB-C input have a USB 3.x option or do they all limit all USB to 2.0? If the latter, then one might try squeezing in some alternative USB-C/MST hubs inside the iMac.

 

[ItsAShaunParty]

Hey all,

I'm getting cold feet.

I picked up a 2017 iMac 27" (LM270QQ1 SD(C1)) for $200 — i5 3.4GHz, 16GB RAM, Radeon Pro 570, 1TB Fusion. The plan was to convert it for use with my new M4 Mac Mini.

I’ve got solid tech experience (did IT at my university, worked at the Apple Store), but I’m not a hardware modder. I recently did a simple 21.5" conversion — just hooked up a board and screen. With this 27", I’d love to retain more features: the speakers (which are excellent), mic, camera, and keyboard controls.

But here’s the thing — I’m cheap. That R1811 board costs $250+, which is hard to justify. And I'm not good at soldering, so the speakers and stuff could be challenging to piece together.

So I started wondering… should I just reattach the screen and use AirPlay or screen sharing? I even bought a dummy 8K HDMI plug and can connect via Ethernet for minimal lag. This video made it seem fine. Not great. But fine. Dumb idea?

As long as I'm being honest — don't judge me — I looked into Luna Display. It doesn't seem like a horrible option.

Again, I just want something for my Mac Mini M4. It seems like Luna could accomplish this quite easily. Then maybe in the future I could find a discounted R1811 and go for it.

It would save hundreds of dollars and a few hours or more of work. Oh, choices.

Thoughts?

Also, I have this 8 K dummy HDMI. Can I use that instead of buying the Luna dongle? What is that dongle? Man, I'm so cheap. I gotta admit, Apple brings out my cheapness. I always feel like they're trying to rip me off, so it makes me feel like I need to beat them at their own game.

 

[marshes]

YMMV and others may have better ideas, but I simply used pincers to snap off the last part of the control strip containing the power button, and connected the wires from the iMac's power button to wires 5 (GND) and 8 (PWR) on the control strip. It's fiddly, but it works, and everything fits. The only downside is you obviously lose the power indicator LED – there is no external indicator of whether the board is on, off or even powered.

hey RDCh, when you connected to wires 5 and 8, how did you go about doing this? Presumably I can just cut wire 8 and solder directly to it, but for the ground / wire 5, did you splice in the iMac power button wire? Read elsewhere in the forum the ground has to remain connected for the other buttons to work since the entire board shares the same ground connection? I might see if I can track down a quick splice or vampire connector so I can leave wire 5 in tact before I cut the end of the board off. Any idea what gauge these little SA1 control board wires are?

 

[PaulD-UK]

@marshes "Any idea what gauge these little SA1 control board wires are?"

It's a JST PH connector, which is rated for 24-28AWG wire gauge.

 

[PaulD-UK]

@ItsAShaunParty
The main problem with using the methods described in your linked video is that everything in the video requires a Mac laptop to control the second screen, because the laptop has it's own boot screen.

Your M4 mini would be booting without a display attached unless you already have proper external monitor attached to it to show boot options and login screen.

I would think that you would only get Luna Display to display 5K at a reduced Hz rate, and with increased latency.
All this throws away the main advantage of using an iMac screen panel as an external monitor – 5K sharpness with no latency....

Your choice. 😉

"What is that dongle? Man, I'm so cheap."

In order to use software to drive an external monitor, the Mac has to be connected to a 'dummy display' dongle, which tricks the Mac's GPU into outputting a display signal at the correct resolution. This signal is then sent to the external monitor using software over USB or a WiFi/ethernet network, rather than a DP or HDMI video cable.

 

[PaulD-UK]

@joevt "Do any of the display boards with a USB-C input have a USB 3.x option or do they all limit all USB to 2.0? If the latter, then one might try squeezing in some alternative USB-C/MST hubs inside the iMac."

No. All the various conversion boards started out as 4K/120 gaming monitors, with firmware updated to support 5K/60.
None of them try to support anything more than USB 2 connectivity to any inbuilt USB hub.
The ones with USB 3.x hubs all have a USB-B input for the USB 3.x uplink, and only USB 2 from theUSB-C video uplink.

DP 1.4 MST output is supported on a couple of high-end boards, but for Windows use only.

Running at a reduced bit-rate at less than 4.4.4 10 bits defeats the primary goal of using Apple's iMac 5K screen panel at the best resolution it offers... 😉

 

[shijan]

GIVIFENI confirmed that they send me wrong model. Now i am thinking maybe keep this low cost board for test purposes and asked them:
"Is it possible to connect this board to other panel without changes in firmware?"
GIVIFENI reply:
"Can connect to other screens"

They also ask to test this board with my panel. Guess without real life test they are not sure if it really will work with this newest panel

Replacement board arrived. Will test it soon...
P.S. Some note for those who attempt to use too old iMacs - don't forget that from tech specs any IPS panel with LED backlight guaranteed lifetime is 30000 hours (tested at 50% brightness). This is near 3.4 years. Older panels with CCFL lamps backlight where 50000 hours.

 

[razmanugget]

@ItsAShaunParty

You got an amazing deal on the iMac. I bought the same for about $350 and was able to sell the guts (motherboard, ram, fusion...) for $135. If you do the same, your panel is nearly free.

I did one conversion with a JRY-W9RQUHD-FA1 video board which was $190. And another conversion with the AA1 for $100. I don't have them set up side-by-side yet, but the picture quality seems about the same to me after I got everything dialed in on each. I do web design work and I see no difference between 8 & 10 bit.

The only downside I see with the AA1 board is that the firmware is old (on mine) and it's kind of janky when it powers off or when the computer enters standby mode. I need to unplug and replug in a magical sequence I still haven't quite figured out. Sometimes it takes me a full minute to get the monitor back up.

I did find a solution with ChatGPT though - to prevent the auto sleeping on power adapter when the display is off. The AA1 board is now working fairly well, but it still doesn't pop up as fast as the FA1.

I use these monitors only for the displays with external power supplies.

If you want to save money, the AA1 board is pretty decent. If you want a better experience and have the money for it, get the FA1 (newer/better firmware too). If you want the full experience with sound, usb, pd... yeah, the R1811 board is for you.

Not sure if that helps, but it's my opinion so far.

 

[kevinherring]

An update on my 21.5" 4K + R9513 v5 build, and a question for the brain trust.

I still have not been able to get the DisplayPort inputs working. The HDMI works fine, so I am using that.

However, I have another problem. The native resolution of the "4K" iMac is actually 4096 x 2304, which is non-standard. However the closest that the driver will accept is 4096 x 2160. I've tried using a BetterDisplay and creating a custom resolution but it won't let me select it. I've tried editing the default resolution, native resolution and so on, but no joy.
Interestingly the EDID does show the correct value (4095 is the maximum value in EDID which is why it doesn't show 4096):

  Detailed Timing Descriptors:
    DTD 1:  4095x2304   59.989710 Hz 455:256  140.376 kHz    590.000000 MHz (596 mm x 335 mm)
                 Hfront   36 Hsync  20 Hback   52 Hpol P
                 Vfront    3 Vsync   5 Vback   28 Vpol N

It's not the end of the world, I just end up with 144 un-used rows of pixels, but it is annoying.

Any ideas?

 

[shijan]

Any ideas?

You can try to export EDID.bin file using BetterDisplay and edit it using AW EDID Editor. Then you need somehow upload file back to display. Seems uploading is possible only using Windows EDID/DisplayID Writer, but i didn't researched this question it yet. I find info in this discussion

https://www.reddit.com/r/Monitors/comments/13zeivg/is_edid_information_unique_to_each_device

I personally started to search for EDID editing options because my JRY-W9RQUHD-FA1 board attached to LM270WRA-SSA1 panel don't have Display Serial Number, and if use more than one display it could be problematic in future to create custom ICC profile for each display because seems DisplayCAL application rely on Display Serial Number to detect displays.

 

[Aiwi]

Hey all,

I'm getting cold feet.

I picked up a 2017 iMac 27" (LM270QQ1 SD(C1)) for $200 — i5 3.4GHz, 16GB RAM, Radeon Pro 570, 1TB Fusion. The plan was to convert it for use with my new M4 Mac Mini.

I’ve got solid tech experience (did IT at my university, worked at the Apple Store), but I’m not a hardware modder. I recently did a simple 21.5" conversion — just hooked up a board and screen. With this 27", I’d love to retain more features: the speakers (which are excellent), mic, camera, and keyboard controls.

But here’s the thing — I’m cheap. That R1811 board costs $250+, which is hard to justify. And I'm not good at soldering, so the speakers and stuff could be challenging to piece together.

So I started wondering… should I just reattach the screen and use AirPlay or screen sharing? I even bought a dummy 8K HDMI plug and can connect via Ethernet for minimal lag. This video made it seem fine. Not great. But fine. Dumb idea?

As long as I'm being honest — don't judge me — I looked into Luna Display. It doesn't seem like a horrible option.

Again, I just want something for my Mac Mini M4. It seems like Luna could accomplish this quite easily. Then maybe in the future I could find a discounted R1811 and go for it.

It would save hundreds of dollars and a few hours or more of work. I am uncertain how to accomplish.

Thoughts?

Additionally, I have an 8 K dummy HDMI. Can I use that instead of buying the Luna dongle? What is that dongle? Man, I'm so cheap.

I used the Luna Display for a while. 5K 45Hz feels pretty bad to be honest. I ended up not using it as often as I'd wanted to, as it:

• Felt a bit unresponsive, even using thunderbolt or ethernet
• Is dependent on the software running well
• You'll need two keyboards and two mice
• Both computers will have to be fully booted and logged in
• and more...

Plus, the Luna Display isn't exactly cheap. You're paying quite a lot of money for a mediocre solution. (Compared to converting the iMac)

After installing the R1811, the iMac feels like a real 5K monitor (which it of course is).

If it feels overwhelming, just do one thing at a time. Just install the driver board and tape the glass to the case using regular transparent packing tape. If you 1 month later feel the urge to add the speakers to the mix, do so then.

 

[shijan]

GitHub - Akemi/macOS-edid-modification: How to obtain the EDID under macOS, modify and override it

How to obtain the EDID under macOS, modify and override it - Akemi/macOS-edid-modification

github.com

 

[kevinherring]

You can try to export EDID.bin file using BetterDisplay and edit it using AW EDID Editor. Then you need somehow upload file back to display. Seems uploading is possible only using Windows EDID/DisplayID Writer, but i didn't researched this question it yet. I find info in this discussion

https://www.reddit.com/r/Monitors/comments/13zeivg/is_edid_information_unique_to_each_device

I personally started to search for EDID editing options because my JRY-W9RQUHD-FA1 board attached to LM270WRA-SSA1 panel don't have Display Serial Number, and if use more than one display it could be problematic in future to create custom ICC profile for each display because seems DisplayCAL application rely on Display Serial Number to detect displays.

Thanks for this. I've tried playing with these and I have made some progress.

It seems that the highest value that EDID supports in the "Detailed Descriptor" is 4095 and not 4096 (12 bit number). The EDID on the R9153 board declares 4095, but as it isn't divisible by 8, I assume MacOS thinks this is an error and discards it as an option. Therefore if I set my native resolution to 4088 by 2304 it works! I'm losing 8 columns of pixels but that isn't noticeable, and I can live with it. Hurahh!

I suspect I wouldn't have this problem with the DisplayPort if it worked. Also the backlight is still really dim, so I still haven't finished with this one.

 

[shijan]

EDID extraction and limited modification also possible using Hackintool
https://github.com/benbaker76/Hackintool/releases

 

[shijan]

Here is more detailed description of the problem with similar or empty EDID serial numbers in multi monitor setups https://notes.alinpanaitiu.com/Weird monitor bugs It is even more confusing situation because there are two places where two different serial numbers could be stored and required by different apps.

 

[Klaazz]

Hi, want to ask if I can use this board with a 24v 8a power supply or must it be 12v ?

 

[PaulD-UK]

@Klaazz The JRY-W9CUHD-AA1 is sold by some vendors with a 24V PSU, so like all JRY 5K boards that is the best voltage to use, but it will work with 12V.