I was just looking at this one too, but there’s very little information about it online. Any ideas if this would work with MacOS?
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
DIY 5k Monitor - success :-)
- Thread starter fiatlux
- Start date
- Sort by reaction score
Thanks for the output. I didn't realize you were using an Apple Silicon Mac. AllRez provides more info for Intel Macs. I need to update for Apple Silicon. Even then it would probably be missing some info. The info for Apple Silicon is gathered from the IO Registry. It includes a list of TimingElements (resolution / timing). There's an indicator
DPTimingModeId that points to the current TimingElement. There's a list of ColorElements (depth, encoding, colorimetry, dynamic range, DSC support). Each TimingElement has a list of ColorModes which I assume is a subset of ColorElements.I suppose having color info seperate from timing info is supperior to the method used on Intel Macs. But there are a couple problems:
- There doesn't appear to be a way to know which ColorElement is the current ColorElement
- There's no way to match a TimingElement with a mode returned by any of the CG* APIs.
Maybe there's an API I don't know about that solves those problems.
Anyway, I don't see any DSC support in the output (
SupportsDSC = 0). 5120x2880 does seem like a valid mode. None of the modes are tiled (IsSplit = 0). Therefore, it's probably connected using HBR3 link rate which would limit you to 8bpc unless you switch pixelEncoding from RGB to 4:2:2 or 4:2:0.I saw this info as well.
There seem to be two different board layouts, both labelled H18.
I'm not sure what to make of it all. More claims, more confusion
190.0US $ |27 '' Imac A1419 A2115 5k Lcd Controller Dp 1.4 Type-c Driver Board Diy Monitor Kit For Lm270qq1 Lm270qq2 Screen Test Mainboard - Laptop Lcd Screen - AliExpress
Smarter Shopping, Better Living! Aliexpress.com
200.0US $ |Monitor Controller Board Imac | Monitor Driver Board Imac | Imac A1419 Lm270wq1 - 27 '' - Aliexpress
Smarter Shopping, Better Living! Aliexpress.com
This pictures in the first (cheaper) link are stamped 'Support iMac 27...'
There is quite a lot of small print info:
Model : Haijing T18 (DP1.4 Type-C) Max.resolution：5120*2880 @60HZ 4K@144HZ
Haijing T18 motherboard, a new all-in-one LCD motherboard that integrates LED backlight driver and the most popular Type-C interface function.
SG18MW_2P2H_KOE1 is a multi-function full HD high refresh rate display driver board, supports DSC (Display Stream Compression) function, single DP1.4, HDMI2.1 can transmit lossless 4K 144Hz (12bit) UHD images, HDMI2.1 interface can support PS5 4K 120Hz.
Support HDR high dynamic lighting rendering image output (High-Dynamic Range), which can provide more dynamic range and image details.
The LED screen backlight drive current hardware can set the maximum output current to 900mA (DC24V input), and the LED screen backlight output current below 900mA can also be adjusted and controlled by software to control the output drive current. The LED screen backlight driving voltage automatically adjusts the output according to the LED light string load of the LED screen, and the maximum backlight power is 35W. The DC input voltage is 12V/24V, the screen voltage can be 12V/10V, with headphone output, 2-way power amplifier output within 5W (8Ω speaker).
It can complete the DP signal or HDMI signal or Type-C output from the PC to the LCD module.
The Type-C port also supports external fast charging of the PD protocol...
Last edited:
Do you mind saying what the rough VAT/import/custom duties to the UK where? I have a 2013 A1419 case and a 2015 27" display already. I just can't bring myself to order a driver board when I think I'm going to get savaged by Her Majesty's Customs Service and I don't know how bad that will...To answer my own question, I found an advertiser ('sunnyqshop' from China) on eBay UK offering both R9A18 and R1811 boards, so I was able to get a R1811 kit delivered (in a few days under two weeks) with no problems whatsoever. No PSU was included, which is fine by me as I prefer to source one with known specifications.
Doing a quick lash together on a table with my M1 mini it looks excellent via a single TB3 cable, driving a new LM270QQ1 (D1) iMac Pro panel that I got in an auction a while ago.
I only have a 20v PSU to hand but that seems to drive the display fine (with no usb-c PD needed).
The vendor asked for the panel details (D1) before preparing the kit to ship, and my R1811 V4 board has V04 firmware, and identifies itself as G1-27.
It will take a few days/weeks? to get a proper PSU and iMac case together (and fit a new sit/stand desk mechanism with VESA arm) so I can finish the assembly properly, and run some more tests.
But compared to the Dell U3014 that I currently have it looks amazing.
I had the same worries, but the whole transaction was as simple as any other eBay purchase.
The parcel arrived 12 days later, delivered by Royal Mail (tracked) , just like any other ordinary mail, and that was that. No extra charge.
That was my experience.
The parcel arrived 12 days later, delivered by Royal Mail (tracked) , just like any other ordinary mail, and that was that. No extra charge.
That was my experience.The Ebay ad says Duties are buyers responsibility so I guess you got lucky? hey ho, will ponder more…I had the same worries, but the whole transaction was as simple as any other eBay purchase.
The parcel arrived 12 days later, delivered by Royal Mail (tracked) , just like any other ordinary mail, and that was that. No extra charge.
Not sure if this is the right place to ask this question but it's worth a shot. I'm generally pretty tech-savvy but not all the time, so forgive me if this is something obvious I'm missing.
I bought the U84 conversion board for my 2014 5k iMac. I've hooked everything up and I'm super happy with the brightness, the colors, and the sharpness of everything. The only problem is that when I play video at less than 4k, mostly from Plex, it looks absolutely atrocious. I've tried multiple cables, and I've tried every scaling option available on my Macbook (M1 Air.) Does anyone have any ideas? Watching video is like 90% of the reason I put this build together. Thanks in advance
I bought the U84 conversion board for my 2014 5k iMac. I've hooked everything up and I'm super happy with the brightness, the colors, and the sharpness of everything. The only problem is that when I play video at less than 4k, mostly from Plex, it looks absolutely atrocious. I've tried multiple cables, and I've tried every scaling option available on my Macbook (M1 Air.) Does anyone have any ideas? Watching video is like 90% of the reason I put this build together. Thanks in advance
I'm not familiar with the U84, any more information on this?
What is your connection? Is it actually 5K?
The connection to the display doesn‘t discern between the normal UI and video playback so if the rest is sharp, the player is the culprit.
What player are you using and are you sure the video is not transcoded?
With a little bit of distance, for me, proper 1080p content looks really good and not much inferior to 4K.
Last edited:
Hey, sorry I mixed up the model numbers. It's the u49 one from Aliexpress. The video looks totally fine playing on my Macbook Air but looks horrendous on the iMac. Not sure if there's an upscaling setting I am missing or something but I do feel there's an issue beyond the player, especially because the videos look great on every tother device including my 65 inch tv, but I could be wrong, though. I appreciate the response.
It's important to make sure that the LCD is actually running at 5K resolution and that it isn't being scaled to a non-native resolution like 4K. If it were, this would make the image quality look fuzzy and not crisp at all. What computer is connected to the display, and what cables are you using? Have you confirmed in the "About this mac" Displays section that the screen resolution is actually 5K (5120x2880)?
About This Mac > Displays isn’t always reliable in my experience. Use AllRez, SwitchResX or the driver board’s OSD (if possible) to check the resolution the display is running at.
Last edited:
Converted my late 2015 5k iMac to a stand alone monitor using the R9A18. I'm getting 5k at 60hz using a single TB to DP 1.4 cable with an M1 mac mini. One quirk is if the computer goes to sleep it'll wake up at 4k and I have to reset the board to the default settings to get 5k back. Restarting doesn't fix this. If I shut down the computer it will be at 5k when it boots up. Other than that it's great. Glad I could save this screen from the trash heap.
The R9A18 isn't DP 1.4 capable. If you get 5K 60Hz via a single DP cable, then its just YUV not RGB: #283
Maybe, that's why it falls back to 4K after sleep - because 4K is possible in RGB via DP 1.2.
Look at this post: #280
What does it say for you under "Color Format"?
In your case, the R1811 would have been the better choice.
Last edited:
At least now you know how to really get the most out of it.
edit: I stand corrected. Two displays ≠ one dual-link SST display.
Last edited:
Try a chroma sub sampling test, it won't look great for coloured text on coloured background.
https://www.rtings.com/tv/learn/chroma-subsampling
What is the firmware version on the R9A18? You can find it at the top right corner of the OSD menu.
Is the input source set to Auto, DP1 or DP2? If it's Auto, try setting it to the DP input you are using.
Have you tried disconnecting and reconnecting the cable from the Mac mini to test if it goes back to 5K when it happens?
Do you have SwitchResX or other similar apps installed?
M1 Macs can also run a dual-link SST display without a Thunderbolt adapter since they have more than one Thunderbolt port.
It's running firmware version 06. Setting the input to DP1 fixed the issue with it waking from sleep at 4k. Thanks!
Hey guys new to this thread and project. I ended up ordering one of those new T18 boards. I'm going to test it out. Any particular tests you'd like me to run on it once I get it?
I'm sitting on a extra LG 5K screen (pulled from a broken LG Ultrafine 5k monitor) deciding which control board to get. Which 5k screen model are you using with the T18?
I'm interested in color fidelity and if there are any wake-from-sleep issues (monitors switching places, black screen, off-colors upon wake, etc.)
Thanks for taking the jump; looking forward to your update!