DP/USB-C/Thunderbolt 3/4 to HDMI 2.1 4k@120hz RGB4:4:4 10b HDR with Apple Silicon M1/M2/M3 now possible !

[spehero]

Hi all! Thanks for this thread, big time!

So I've CableMatters HDMI to USB-C working with MacBook Pro M1 and LG C2.

However, a significant delay is often before the image appears on the LG C2. I have put up with it for a while, but I can't tolerate it anymore. Has anyone else experienced this issue, and if so, is there a solution?

I have the Macbook power connected all the time, with turn-off display after 1 hour.

When I turn on the TV and my Mac is awake, it takes a few minutes for the signal to show up on the TV. Until then, the screen displays a 'no signal' wallpaper. Although the sleep-from-wake feature doesn't work, my primary concern is the delay in the signal display.

Thanks!

 

[Igorjos]

I have test this one and it does not work. Also another guys test it and it does not work.

Yes, I saw this posts. I thought maybe someone managed to get it working. I just saw that purfikt in post below (post nr.#1,125) explained that it will work after firmware flashing.

 

[Igorjos]

Hi all! Thanks for this thread, big time!

So I've CableMatters HDMI to USB-C working with MacBook Pro M1 and LG C2.

However, a significant delay is often before the image appears on the LG C2. I have put up with it for a while, but I can't tolerate it anymore. Has anyone else experienced this issue, and if so, is there a solution?

I have the Macbook power connected all the time, with turn-off display after 1 hour.

When I turn on the TV and my Mac is awake, it takes a few minutes for the signal to show up on the TV. Until then, the screen displays a 'no signal' wallpaper. Although the sleep-from-wake feature doesn't work, my primary concern is the delay in the signal display.

Thanks!

Check this one: https://www.reddit.com/r/OLED_Gaming/comments/vt6w8g MAYBE it will help you to solve your problem.

 

[Zorast]

Check this one: https://www.reddit.com/r/OLED_Gaming/comments/vt6w8g MAYBE it will help you to solve your problem.

U can also use the always on function for the LG. And there are also a lot of settings in better display for that.

 

[Igorjos]

Cable Matters has a page that lists the five adapters that work. Also, it sounds like they only sell adapters with VMM7100 now. Here is the page: https://www.cablematters.com/Blog/HDMI/how-to-get-4k120hz-with-mac

It looks like the one you are asking about is: 48Gbps USB-C® to HDMI Adapter with 100W Power Delivery (SKU 201428). If so, then yes it will work after you flash the firmware. Just contact Cable Matters and ask for the custom firmware specific to that adapter. You will need Windows running on a device with USB-C to Displayport feature. I used a work laptop to do it.

Quote about only selling newer adapters now:
"If you already have a newer Cable Matters adapter or bought a new one specifically to enjoy 4K 120Hz on your Mac, then you’ll have one running the newer VMM7100 firmware. Since Cable Matters doesn’t mass produce any adapters using the custom firmware required for 4K 120Hz on M1 and M2 Macs, you’ll still need to contact Cable Matters directly to get it."

Quote about the five adapters from Cable Matters that work:
"Cable Matters has a custom firmware that is fit for the following five Cable Matters Products:

1. 48Gbps USB-C® Adapter Supporting 8K Video (SKU 201388-A)
2. USB-C® to 8K HDMI Cable (SKU 201362-A)
3. Foldable USB-C® to 8K HDMI Adapter in Black (SKU 201398)
4. USB-C® Multiport Adapter with HDMI (SKU 201310)
5. 48Gbps USB-C® to HDMI Adapter with 100W Power Delivery (SKU 201428)

All of these adapters have been tested with the new custom firmware on M1 and M2 MacBooks to confirm that they do enable 4K at 120Hz."

Thank you very much Bro! Very clear and informative. I will contact Cable Matters for a custom firmware before buy one.

 

[Zorast]

Thank you very much Bro! Very clear and informative. I will contact Cable Matters for a custom firmware before buy one.

This is not right, there are adapters that will not work. If there is adapters that is verified from guys here or from me, they are listed in the OP.

 

[Igorjos]

This may be an off-topic question. I have asked before: Anyone is using alike setup for color grading in Davinci resolve, or it is not a good idea or i need to go this root (use calibration tool and software with blackmagic decklink capture card mentioned here

.Or it is not worth that hustle and money to invest. How i understand you will not get calibrated colors if use just adapter with Hdmi cable due to the mac os color profiles.

 

[Igorjos]

This is not right, there are adapters that will not work. If there is adapters that is verified from guys here or from me, they are listed in the OP.

And do you think Cable Matters also can not confirm functionality information?

 

[Zorast]

And do you think Cable Matters also can not confirm functionality information?

CM can not test all devices. But we can test it on our devices. This Firmware is Beta and they write its not ready for mass production. This Firmware is based in our solution to get 4@120hz workable but it is not 100% ready for all devices. There are some cases they claim it works on there side but on our side it does not! So the only cable that we be 100% sure are working are that one are listed in the OP. The CM flexible short one, the one with PD and the one with longer USB-C Cable does not work till i write this comment. The best way is to use the female one with an TB4 Station like me did and others too. With an TB4 station u will also not have the Sleep issue.

 

[Igorjos]

CM can not test all devices. But we can test it on our devices. This Firmware is Beta and they write its not ready for mass production. This Firmware is based in our solution to get 4@120hz workable but it is not 100% ready for all devices. There are some cases they claim it works on there side but on our side it does not! So the only cable that we be 100% sure are working are that one are listed in the OP. The CM flexible short one, the one with PD and the one with longer USB-C Cable does not work till i write this comment. The best way is to use the female one with an TB4 Station like me did and others too. With an TB4 station u will also not have the Sleep issue.

Thank you! Everything is clear to me now.

 

[PieroPontra]

Wonderful job here guys, much appreciated!
Now... anyone tried to use this firmware update to drive an 8K 60Hz monitor instead of 4K 120Hz? Don't wanna swap my Mac Studio M1 Max for the newer M2 Max only for it if possible.

 

[joevt]

Wonderful job here guys, much appreciated!
Now... anyone tried to use this firmware update to drive an 8K 60Hz monitor instead of 4K 120Hz? Don't wanna swap my Mac Studio M1 Max for the newer M2 Max only for it if possible.

8K60 is twice the bandwidth of 4K120.

 

[PieroPontra]

8K60 is twice the bandwidth of 4K120.

Yep, sure... I was asking since it's supported on windows. So it's a no go?

 

[Zorast]

8K60 is twice the bandwidth of 4K120.

I think 8k@60hz 4:4:4 is not possible with HDMi 2.1 iam right? Or only with DSC possible.

 

[joevt]

I think 8k@60hz 4:4:4 is not possible with HDMi 2.1 iam right? Or only with DSC possible.

Correct.

8K60 HDMI is 2376 MHz. This requires DSC@8bpp for 24Gbps, DSC@11bpp for 32Gbps, DSC@14bpp for 40Gbps, DSC@17bpp for 48 Gbps
DisplayPort 1.4 requires DSC@10bpp.

If you use CVT-RB2 timing, then 8K60 is 2106 MHz so you can reduce the compression for that. DisplayPort 1.4 can do that with DSC@12bpp. 12bpp is the default DSC target bpp for macOS. I don't know if macOS can do DSC @ less or more than that.

4:2:0 8bpc is also 12bpp.

 

[Zorast]

Yeah we have to wait for TB5 and DP 2.0 for better and faster connections. Iam waiting for TB5 to use an eGPU RTX4090 on Windows machines.

 

[Kosimo]

Just to let you know guys about my absolute failure here.


After being so disheartened with my Mac Mini M2 and an LG OLED C2 being totally confined to 4K@60Hz with a lagging HDR and YCBCR422 8-bit, I tried numerous USB-C HDMI 8K adapters to no avail.


Then I stumbled upon this remarkable post (by the way, thank you so much to everyone involved in this!). However, after acquiring the correct CM adapter based on VMM7100, I encountered numerous challenges locating a PC with a suitable USB-C output capable of functioning while connected to an external monitor to utilize the update tool. I utilized the firmware from the first post, and strangely, my adapter arrived with newer firmware than the one provided, specifically 7.02.120. As a result, I had to downgrade the adapter. Despite numerous failed attempts, I was finally able to successfully "downgrade" the firmware to match the one posted in the first post, receiving a message confirming the update and a request to restart the device. And then it simply vanished, and the update tool was unable to detect it again. Upon returning home and connecting it to my Mac, it was unresponsive. Dead.


Despite all my efforts, I am still unable to achieve a satisfactory output from my Mac Mini M2. I will be returning the dongle to Amazon in the hope of obtaining a refund and will not attempt any further solutions (having already purchased three different devices before discovering this post).


I am now seriously considering switching back to a PC or perhaps trying out the Mac Mini M2 Pro, which has an HDMI 2.1 port, but the significant price difference makes it rather absurd to me.


An exasperated user

 

[Zorast]

Just to let you know guys about my absolute failure here.


After being so disheartened with my Mac Mini M2 and an LG OLED C2 being totally confined to 4K@60Hz with a lagging HDR and YCBCR422 8-bit, I tried numerous USB-C HDMI 8K adapters to no avail.


Then I stumbled upon this remarkable post (by the way, thank you so much to everyone involved in this!). However, after acquiring the correct CM adapter based on VMM7100, I encountered numerous challenges locating a PC with a suitable USB-C output capable of functioning while connected to an external monitor to utilize the update tool. I utilized the firmware from the first post, and strangely, my adapter arrived with newer firmware than the one provided, specifically 7.02.120. As a result, I had to downgrade the adapter. Despite numerous failed attempts, I was finally able to successfully "downgrade" the firmware to match the one posted in the first post, receiving a message confirming the update and a request to restart the device. And then it simply vanished, and the update tool was unable to detect it again. Upon returning home and connecting it to my Mac, it was unresponsive. Dead.


Despite all my efforts, I am still unable to achieve a satisfactory output from my Mac Mini M2. I will be returning the dongle to Amazon in the hope of obtaining a refund and will not attempt any further solutions (having already purchased three different devices before discovering this post).


I am now seriously considering switching back to a PC or perhaps trying out the Mac Mini M2 Pro, which has an HDMI 2.1 port, but the significant price difference makes it rather absurd to me.


An exasperated user

This must work. Did u use the correct Adapter? Did you read the OP correctly ?

 

[theorist9]

I'm wondering why, when M2/M3 Pro/Max's are driving a higher-bandwidth display (8k@60 or 4k@240), this reduces, by one, the total number of displays they can drive. That would tell us what these chips are doing in order to drive such displays.

Specifically consider the M2/M3 Pro's. Based on Apple's spec's, these can either drive two lower-bandwidth displays (2 x 6k@60 or 1 x 6k@60 + 1 x 4k@144), or a single higher-bandwidth display (8k@60 or 4k@240). [We see a similar one-display decrease when the M2 and M3 Max MBP's are driving a higher-bandwidth display.]

I pasted an annotated die shot of the M3 Pro below. You can see that chip has two external display engines, which is why it can drive two external displays. [It also has a smaller internal display engine for the laptop screen, which is not annotated.]

Why do the M2/M3 Pro's lose their ability to drive a 2nd external display when driving an 8k@60 or a 4k@240? These are the only two possibilities I can think of, but I have no idea if either one applies:

1) It's bridging the two external display engines together in order to drive that single display.

2) It needs to (and is somehow able to) internally reallocate PCIe lanes to the HDMI port when it drives a higher-bandwidth display, thus leaving it without enough I/O for a 2nd external monitor.

Maybe @joevt has some insight?

(source:

).

 

[joevt]

I'm wondering why, when M2/M3 Pro/Max's are driving a higher-bandwidth display (8k@60 or 4k@240), this reduces, by one, the total number of displays they can drive. That would tell us what these chips are doing in order to drive such displays.

Specifically consider the M2/M3 Pro's. Based on Apple's spec's, these can either drive two lower-bandwidth displays (2 x 6k@60 or 1 x 6k@60 + 1 x 4k@144), or a single higher-bandwidth display (8k@60 or 4k@240). [We see a similar one-display decrease when the M2 and M3 Max MBP's are driving a higher-bandwidth display.]

I pasted an annotated die shot of the M3 Pro below. You can see that chip has two external display engines, which is why it can drive two external displays. [It also has a smaller internal display engine for the laptop screen, which is not annotated.]

Why do the M2/M3 Pro's lose their ability to drive a 2nd external display when driving an 8k@60 or a 4k@240? These are the only two possibilities I can think of, but I have no idea if either one applies:

1) It's bridging the two external display engines together in order to drive that single display.

2) It needs to (and is somehow able to) internally reallocate PCIe lanes to the HDMI port when it drives a higher-bandwidth display, thus leaving it without enough I/O for a 2nd external monitor.

Unless someone tries it, we don't know for sure that it can't do more than one higher-bandwidth display. Apple said the Vega MPX module can't do three 6K displays but then someone tried it and it works fine.
https://forums.macrumors.com/threads/psa-pro-vega-ii-single-can-power-3x-xdr-displays.2225758/
https://support.apple.com/en-ca/101641

If there's a limit then it's either because Apple added a limit to the driver, or because the hardware is not capable. Why would Apple add a limit to the driver if the hardware is capable? Maybe the hardware is capable only in certain situations. Or maybe the performance drop or power requirements is unacceptable.

PCIe lanes has nothing to do with graphics.

#1 is a reasonable guess. If there's a hardware thingy that can handle x pixels per second and you want to do more pixels than that, then a GPU can use a second hardware thingy.

Here's something about Linux and Intel GPUs doing 8K:
https://lpc.events/event/5/contributions/317/attachments/435/689/XDC2019_8K_Trans_Port_Sync.pptx.pdf
I think there's a related YouTube video.

 

[vikassri]

All , first of all thanks for such a helpful post!

Wanted to share that I was able to get this working with the adapter here from CableMatters with power delivery

Cable Matters Portable 48Gbps USB C to HDMI 2.1 Adapter with 100W Host Charging, 4K 120Hz /8K 60Hz HDR - Thunderbolt 4 Compatible with iPhone 15 Pro Max - Maximum Resolution on Any MacBook is 4K@60Hz https://www.amazon.com/dp/B0CCF9S7TL?ref_=cm_sw_r_apin_dp_TGWX8GVY4DQ6H85V9BTR&language=en-US

I had requested the firmware specifically for this and they sent me this link :

MacOS 4K120Hz (201428)

3 files sent via WeTransfer, the simplest way to send your files around the world

go.wetransfer.com

I updated the firmware and can confirm 120hz on my external monitor.

HTH , let me know if you have any questions!

 

[Zorast]

All , first of all thanks for such a helpful post!

Wanted to share that I was able to get this working with the adapter here from CableMatters with power delivery

Cable Matters Portable 48Gbps USB C to HDMI 2.1 Adapter with 100W Host Charging, 4K 120Hz /8K 60Hz HDR - Thunderbolt 4 Compatible with iPhone 15 Pro Max - Maximum Resolution on Any MacBook is 4K@60Hz https://www.amazon.com/dp/B0CCF9S7TL?ref_=cm_sw_r_apin_dp_TGWX8GVY4DQ6H85V9BTR&language=en-US

I had requested the firmware specifically for this and they sent me this link :

MacOS 4K120Hz (201428)

3 files sent via WeTransfer, the simplest way to send your files around the world

go.wetransfer.com

I updated the firmware and can confirm 120hz on my external monitor.

HTH , let me know if you have any questions!

Plz send confirmation that u have 4k@120hz RGB 4:4:4

 

[acmac]

All , first of all thanks for such a helpful post!

Wanted to share that I was able to get this working with the adapter here from CableMatters with power delivery

Cable Matters Portable 48Gbps USB C to HDMI 2.1 Adapter with 100W Host Charging, 4K 120Hz /8K 60Hz HDR - Thunderbolt 4 Compatible with iPhone 15 Pro Max - Maximum Resolution on Any MacBook is 4K@60Hz https://www.amazon.com/dp/B0CCF9S7TL?ref_=cm_sw_r_apin_dp_TGWX8GVY4DQ6H85V9BTR&language=en-US

I had requested the firmware specifically for this and they sent me this link :

MacOS 4K120Hz (201428)

3 files sent via WeTransfer, the simplest way to send your files around the world

go.wetransfer.com

I updated the firmware and can confirm 120hz on my external monitor.

HTH , let me know if you have any questions!

Yes, I have the same CM adapter and also received the firmware for it directly from CableMatters. I'm using it for 5120x1440 120/144Hz w/HDR and it works. However, the wake from sleep and random disconnects are very disappointing. Totally an Apple issue, as I use the same adapter with the same monitor on a Windows laptop without issue. With Windows, the monitor has always woken up and displayed an image and has NEVER randomly lost connectivity.

Also to note, changing the refresh rate down to 60Hz doesn't solve the wake/disconnect issue either so I doubt its a bandwidth problem. I truly believe Apple will never address this issue just because its gone on for sooooo long.

The great thing about the 201428 adapter is that its PD with the stock 96w charger for my MPB M1 Max passes through 94W. When I originally had a CM usb-c >> DisplayPort 1.4 multiadapter, only 87W were passing through. But this whole wake/disconnect issue has me seriously considering going back to a DisplayPort adapter, if of course that would resolve those issues. Haven't determined if it would though. Also, CM doesn't appear to have a usb-c >> displayport 1.4 adapter w/PD only, as the only ones w/ PD are "multi" adapters.

 

[Eson]

Interesting case:
MacBook Pro M1 14"
Cable Matters USB-C adapter 201388-A, delivered from Amazon with .120 firmware
LG C2 42"
Yiwentec 8K HDMI Cable

No issues with getting 4k120hz from a HP Windows Laptop with 12th Gen Intel CPU with XE GPU with the same adapter and cable.

With the Macbook however can't get anything other than max 60hz listed in refresh rate :/

 

[acmac]

Interesting case:
MacBook Pro M1 14"
Cable Matters USB-C adapter 201388-A, delivered from Amazon with .120 firmware
LG C2 42"
Yiwentec 8K HDMI Cable

No issues with getting 4k120hz from a HP Windows Laptop with 12th Gen Intel CPU with XE GPU with the same adapter and cable.

With the Macbook however can't get anything other than max 60hz listed in refresh rate :/

Did you flash the adapter with the custom firmware that enables 4k/120Hz?