DIY 5k Monitor - success :-)

[PaulD-UK]

There seems to be a problem with the Startech Adapter.
Apart from that I think you are getting normal performance, from 2017 Macs which are DP1.2 and which don't support DSC.
The (only) way to get 5K is to use two DP cables, although port DP1 indicates that its DP 1.3, which might support better single cable operation.
I think the most recent firmware for the R9A18 is V06

 

[Sisifox46]

I have problems with my LM270QQ1 SD A3. It's the second board I get and same problem (JRY W9CUHD AA1). May be it's silly but I can't connect the backlit cable. I can't see the way to put them together. I don't know if they really match... the pins from the board seems to be round but the ones on the iMac are flat..

Any help? Thanks!

 

[vistavizion]

There seems to be a problem with the Startech Adapter.
Apart from that I think you are getting normal performance, from 2017 Macs which are DP1.2 and which don't support DSC.
The (only) way to get 5K is to use two DP cables, although port DP1 indicates that its DP 1.3, which might support better single cable operation.
I think the most recent firmware for the R9A18 is V06

Ah! It's all becoming clear! I really appreciate your insight. I'm considering turning these conversions into a side hustle, so it's important that I wrap my head around "end user variables."

https://support.apple.com/en-us/102501... leads to links on what Macs are expected to support. I shall research there.

Cheers!

-Paul NYC

 

[yaosiang]

I have problems with my LM270QQ1 SD A3. It's the second board I get and same problem (JRY W9CUHD AA1). May be it's silly but I can't connect the backlit cable. I can't see the way to put them together. I don't know if they really match... the pins from the board seems to be round but the ones on the iMac are flat..

Any help? Thanks!

You need to apply a little force to push the pins into the backlight connector of the LCD panel. There are 12 pins and 12 holes. They should align. If the backlight does not lit up, it means you got the polarity wrong. Try again by flipping the connector. The connector on the cable that came with your board looks similar to majority of 5K driver boards.

 

[vistavizion]

do you think it’s safe to use it with type C? Is there an option to disable charging over it? I had burned my M1 macs charging port before while using PD over one of the best seller anker hubs so I am kinda scared about. Is there a way to check it whether the surge protection is good enough or not?

"I had burned my M1 macs charging port before while using PD"

Is this something to worry about? I'd like to use this monitor interchangeably with MacBooks and Macs. Would not want to risk damage to either!

Cheers!

-Paul NYC

 

[yaosiang]

"I had burned my M1 macs charging port before while using PD"

Is this something to worry about? I'd like to use this monitor interchangeably with MacBooks and Macs. Would not want to risk damage to either!

Cheers!

-Paul NYC

The R9A18 does not support USB-C / PD (Power Delivery) so it will not charge your MacBook.

 

[PaulD-UK]

@Sisifox46 your 2nd pic, IMG_1004, shows the correct way - the red wires connect to grey wires, not black.

 

[Sisifox46]

I have problems with my LM270QQ1 SD A3. It's the second board I get and same problem (JRY W9CUHD AA1). May be it's silly but I can't connect the backlight cable. I can't see the way to put them together. I don't know if they really match... the pins from the board seems to be round but the ones on the iMac are flat..

Any help? Thanks

You need to apply a little force to push the pins into the backlight connector of the LCD panel. There are 12 pins and 12 holes. They should align. If the backlight does not lit up, it means you got the polarity wrong. Try again by flipping the connector. The connector on the cable that came with your board looks similar to majority of 5K driver boards.

thanks a lot. I did try harder and got it.

 

[PaulD-UK]

Once it’s in (the correct way) use some long life adhesive tape to make sure it stays in.

 

[Sisifox46]

Once it’s in (the correct way) use some long life adhesive tape to make sure it stays in.

Thanks for the advise. I will do it. Almost done. Thanks a lot!

 

[DSTOFEL]

Deleted

 

[Ycbr]

@Aiwi love your approach to keeping things stock.

ive read your build guide many times now but still can’t figure out how you wired the noctua fan and iMac fan using the noctua PWM controller. Particularly how you connected the input of the PWM controller to the R1811’s 12V fan driver (2pin?)

Anyway you can expand on that for me? thanks in advance!

 

[Aiwi]

@Aiwi love your approach to keeping things stock.

ive read your build guide many times now but still can’t figure out how you wired the noctua fan and iMac fan using the noctua PWM controller. Particularly how you connected the input of the PWM controller to the R1811’s 12V fan driver (2pin?)

Anyway you can expand on that for me? thanks in advance!

Thanks!

Sure:

 

[Ycbr]

Thanks!

Sure:

View attachment 2364888

Wow - this is so much clearer than I was expecting. I really appreciate it @Aiwi!

 

[boulala]

Does anyone here know if the JRY-W9CUHD-AA1 Board also has a 12V Fan Header/Pin-Out on the board?
I'm afraid that the board gets a little to hot inside the case and would like to connect the original iMac fan.
I'm using a 24V power supply to power my board. Else i would have to buy a voltage step down and hook that inbetween the power supply and fan.

 

[PaulD-UK]

No 12v power source is obviously available, only 5v on the extra USB socket on the edge of the board next to the outer HDMI socket. The iMac fan will run on 5v at low speed (but still quite noisy with no PWM controller) but it might be too much for the USB socket's power delivery.

24v-12v (or a bit less) converters are readily available.
I used an XL4015 5A 75W DC-DC Adjust Buck Step-down Converter Power Supply Module.
With an HW-585 (or 50K3950) 4-wire PWM controller to run the iMac fan at a silent speed.
The left two modules in this pic, the one on the right controls my R1811 heatsink fan:
https://forums.macrumors.com/data/attachments/1191/1191127-66d83b3228c6da35b670064df1c9c158.jpg

 

[boulala]

No 12v power source is obviously available, only 5v on the extra USB socket on the edge of the board next to the outer HDMI socket. The iMac fan will run on 5v at low speed (but still quite noisy with no PWM controller) but it might be too much for the USB socket's power delivery.

24v-12v (or a bit less) converters are readily available.
I used an XL4015 5A 75W DC-DC Adjust Buck Step-down Converter Power Supply Module.
With an HW-585 (or 50K3950) 4-wire PWM controller to run the iMac fan at a silent speed.
The left two modules in this pic, the one on the right controls my R1811 heatsink fan:
https://forums.macrumors.com/data/attachments/1191/1191127-66d83b3228c6da35b670064df1c9c158.jpg

Thanks, i didn‘t know that the fan also runs on 5V only.
I will try it for a couple of days on the usb socket and see how the power delivery and noise is until i get my new power supply.

 

[DSTOFEL]

I’ve got a late 2015 27 inch iMac that has that gorgeous 5k display. I’m wanting to turn this into a monitor that I can use with a Mac Studio setup as the main display.

After reading through many of the posts on this thread, it seems that the R1811 is the best solution. Is my understanding correct that I can use this board to transform my iMac into a display using this board while still retaining the full performance of the display (ie brightness, colors, etc…)?

If so, is the board in my attachment considered the best option? Or, is there another board that is the top recommendation? I don’t mind paying a bit more for the best solution. Thanks in advance!

 

[PaulD-UK]

The R1811 is the best option for three reasons IMO...

1) Best featured, especially the HDMI 2.1 version, which has more recent firmware. The HDMI 2.1 isn't as fully featured as the USB-C/DP inputs. Also has I/R control.
2) Best, well at least some, documentation, so the support community has some idea how to troubleshoot problems.
3) Best vendor support, with multiple vendors who can support buyers not in China.

The alternative T18 or T19 have more or less the same hardware, and are cheaper, but don't have the same support, and their firmware seems more basic, with no I/R. They can run at 12v, which can be important for some buyers.

The other options all run at 8-bit colour resolution when using a single cable , not the 10-bit of the R1811 and T18/19.

Good luck if you go forward with this project.

Full control of brightness, audio levels etc comes from software like Monitor Control, Better Display or eqMac.

 

[PaulD-UK]

Quote @boulala "Thanks, i didn‘t know that the fan also runs on 5V only."

You can get an adapter to run a 12v fan from a 5v USB-A port:

CRJ 12V Step-Up USB to Dual PC Fans Power Adapter Cable - 24-inch (60cm), Black Sleeved - Full Fan Speed Adapter for 3-Pin/4-Pin Cooling Fans

The CRJ USB to Dual Fan Power Adapter Cable stands out as the first full-speed USB adapter designed to power computer fans, offering unparalleled flexibility in utilizing almost any fan, PWM controller, or compatible device. Equipped with a high-efficiency voltage step-up module, this cable deliv...

www.amazon.com

Then use this controller to reduce the speed:

Noctua NA-FC1, 4-Pin PWM Fan Controller (Black)

Noctua NA-FC1 contrôleur de vitesse du ventilateur 3 canaux Noir

www.amazon.com

See @Aiwi post #1263 above ( the R section of his diagram) for help with wiring.

 

[DSTOFEL]

The R1811 is the best option for three reasons IMO...

1) Best featured, especially the HDMI 2.1 version, which has more recent firmware. The HDMI 2.1 isn't as fully featured as the USB-C/DP inputs. Also has I/R control.
2) Best, well at least some, documentation, so the support community has some idea how to troubleshoot problems.
3) Best vendor support, with multiple vendors who can support buyers not in China.

The alternative T18 or T19 have more or less the same hardware, and are cheaper, but don't have the same support, and their firmware seems more basic, with no I/R. They can run at 12v, which can be important for some buyers.

The other options all run at 8-bit colour resolution when using a single cable , not the 10-bit of the R1811 and T18/19.

Good luck if you go forward with this project.

Full control of brightness, audio levels etc comes from software like Monitor Control, Better Display or eqMac.

Thanks so much for the confirmation on the R1811 and for all of the additional info. This really help!. I’m going to remove the glass off of the iMac this weekend so as to get the model number of the display. I do have one question: If I go with the R1811, T18 or T19 option, my assumption is that I need to disassemble everything inside the iMac (Power supply, speakers, logic board, etc….) and install the new board. Is this correct? Or, are there any components that I need to leave ”in tact” inside the iMac?

 

[Regulus67]

... I need to disassemble everything inside the iMac (Power supply, speakers, logic board, etc….) and install the new board. Is this correct? Or, are there any components that I need to leave ”in tact” inside the iMac?

That is correct.
But you can reinstall the speakers, if you wish to use them. Some of us use the built in speakers.
The camera, wifi and Bluetooth antenna you don't have to touch. Or replace the built in camera.

I would only add.
Be very careful when you remove the two ribbon cables that goes to the display panel from the motherboard. Make sure the clamps are released properly before pulling them out.
Carefully attach the new DP ribbon cable to the motherboard, without bending the end

 

[DSTOFEL]

That is correct.
But you can reinstall the speakers, if you wish to use them. Some of us use the built in speakers.
The camera, wifi and Bluetooth antenna you don't have to touch. Or replace the built in camera.

I would only add.
Be very careful when you remove the two ribbon cables that goes to the display panel from the motherboard. Make sure the clamps are released properly before pulling them out.
Carefully attach the new DP ribbon cable to the motherboard, without bending the end

Thanks so much for the information and the tip on the ribbon cables! The last time I got into the inside of an iMac was my 2008 24 inch iMac when I removed the LCD to replace the hard drive with an SSD and I recall having to disconnect the cables from the board. I think I’ve got everything I need now to start the process

 

[fhall1]

I’ve got a late 2015 27 inch iMac that has that gorgeous 5k display. I’m wanting to turn this into a monitor that I can use with a Mac Studio setup as the main display.

After reading through many of the posts on this thread, it seems that the R1811 is the best solution. Is my understanding correct that I can use this board to transform my iMac into a display using this board while still retaining the full performance of the display (ie brightness, colors, etc…)?

If so, is the board in my attachment considered the best option? Or, is there another board that is the top recommendation? I don’t mind paying a bit more for the best solution. Thanks in advance! View attachment 2365455

Wow - the price has really shot up on that board!

 

[PaulD-UK]

Not in my experience (ie since late 2021).
That price is the price you pay, delivered to your door.
You have to compare all the 'add-ons' if you go for a random AliExp vendor.
The old HDMI 2.0 board is bit cheaper.