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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 !
- Thread starter Zorast
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Good news! We now have a standard DisplayPort 1.4 to HDMI 2.1 adapter from cablematters. I was just provided a new firmware file from them and it works flawlessly. I am using a CalDigit TS4 dock with this adapter plugged into it's DisplayPort out. I have an M2 Max MacBook Pro with an LG CX OLED 48 inch and I am not using better display as it uses the VM7100 chip just like the USB C version. DO NOT USE THE FIRMWARE FROM THE USB C ADAPTER! It will brick your adapter. I have attached the file for the DisplayPort to HDMI adapter below and linked to the amazon link where you can purchase it. Make sure it is model 102101 before you flash this firmware and that it is using VM7100. This is great news for those of us using thunderbolt docks that have DisplayPort 1.4 as we no longer need to use an entire USB-C or Thunderbolt port just for our display out. Hope this helps!
Amazon.com: Cable Matters 8K DisplayPort 1.4 to HDMI 2.1 Adapter with 4K 120Hz or 8K 60Hz, Unidirectional DisplayPort to HDMI 2.1 Cable Adapter in Black, Support for RTX 3080/3090, RX 6800/6900 and More : Electronics
Amazon.com: Cable Matters 8K DisplayPort 1.4 to HDMI 2.1 Adapter with 4K 120Hz or 8K 60Hz, Unidirectional DisplayPort to HDMI 2.1 Cable Adapter in Black, Support for RTX 3080/3090, RX 6800/6900 and More : Electronics
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Wow, incredible. I can finally use my 42" LG C2 with my Mac Studio Ultra at 120hz. THANK YOU. I'm just going to flash the CM USB-C to HDMI 2.1 (male) adapter so I don't need to buy two cables.
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The male variant dont work correctly, its also not listet in the OP
I have noticed that some blogs and youtuber have stolen our solution here and posted it on their own threads. I think that is not okay. They could have at least referenced this thread with credits, but unfortunately they didn't. Well, that's how it is with the internet :/
Hi @AironMan I am XiaoYuan, thank you very much for your method. I have successfully turned on 4K120hz on my Sony OLED TV. Then I want to your article to my video, hoping to get your permission. Thanks again.
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Hello,
I have the Cable Matters 201428 model, with HDMI and 100W PD to Thunderbolt 3/4.
On VmmDPTool Chipset ID was VMM7100, so I started to load the VM7100's custom firmware.
The tool asked me to unplug then replug the device, after that the cable no longer works. I can't even reflash it with the original fireware, VmmDPTool does not recognize it.
Any help ?
Debug Status before flashing :
I have the Cable Matters 201428 model, with HDMI and 100W PD to Thunderbolt 3/4.
On VmmDPTool Chipset ID was VMM7100, so I started to load the VM7100's custom firmware.
The tool asked me to unplug then replug the device, after that the cable no longer works. I can't even reflash it with the original fireware, VmmDPTool does not recognize it.
Any help ?
Debug Status before flashing :
Code:
EDID information
Product ID: GSMC0C8
Serial No: 16843009
CHIP ID: VMM7100
CHIP version: A1
Manufacture date: 39th week of the year 2021
Firmware name: Spyder_fw_DP_CM
Firmware version: 7.02.120
Configuration file version: 064
Bootloader version: 001
Bootstrap setting: 0x08
Active flash bank: 0
JTAG loading: Disabled
Service mode: Service mode
Load speed: 50 Mbps
MCU speed: 300MHz
Firmware image load result: 0x1f, error code: 00
Firmware code loading OK
Configuration block0 loading OK
Configuration block1 loading OK
HDCP 1.4 key check OK
HDCP 2.2 key check OK
Running in firmware
Microsoft Windows 10 (build 9200), 64-bit
AMD64 CPU 8 processor 32bit OS
System name: CP-DELL
Intel GPU
Gpu name: Intel(R) Iris(R) Xe Graphics
Video processor name: Intel(R) Iris(R) Xe Graphics Family
Drive version: 27.20.100.9168
GOP version: 17.0.1052They do not say it's RGB 4:4:4. With 4:2:0 it works sure. There also a change that it only work on Samsung but not on LGs or another Monitors.
well, i have the 7100 adapter, tried the firmware, but i don't have an image on the OLED display.
Even tho the firmware is the correct version 7.02.112
MacStudio dp to hdmi 2.1 , with 7100 adapter.
The only difference is that I use VMware player and not parallels..........
maybe that's the wrong part? (I'm the only one who voted that it didnt work so, its probably me.).
Even tho the firmware is the correct version 7.02.112
MacStudio dp to hdmi 2.1 , with 7100 adapter.
The only difference is that I use VMware player and not parallels..........
maybe that's the wrong part? (I'm the only one who voted that it didnt work so, its probably me.).
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Alright alright alright! 
it works!! hahahaha thank you!! now the only thing i have left is the Dolby Vision mode?!?!?
Cheers!
it works!! hahahaha thank you!! now the only thing i have left is the Dolby Vision mode?!?!? Cheers!
Thank you @AironMan and everyone for getting this to work! I tested this with my M1 Pro MBP and C2 using the CM 201388-A USB-C to HDMI 2.1 adapter and can report 4K 120 RGB 444 works well.
However, I notice that when my MBP goes to sleep it is really hard to wake the display. Some times it wakes with a press of a key and other time I'm forced to disconnect my MBP from the display and even reconnect the power. Even then it is very inconsistent. Is this expected behavior for the VM7100 adapters?
However, I notice that when my MBP goes to sleep it is really hard to wake the display. Some times it wakes with a press of a key and other time I'm forced to disconnect my MBP from the display and even reconnect the power. Even then it is very inconsistent. Is this expected behavior for the VM7100 adapters?
Play with BetterDisplay Settings for wake Displays, its describe in the OP. For me it works best when I disable this feature, but iam using an TB4 Dock.
I got the CableMatters 201398-BLK and noticed a very weird issue with my M1 MB Air. When the lid is open I get YCBCR444 10b and everything works fine, but as soon as I close the lid and use it in clamshell mode I only get YCBCR422 8b..
Has anyone experienced similar issues?
Has anyone experienced similar issues?
Just a quick heads-up, CableMatters support said the following a few days ago:
"About the VRR support, I learned from the team that we may introduce it in an upgraded chipset in the future, but it’s not likely that we can implement it in the VMM7100 chipset."
So it seems our speculation is likely correct. Also, BD showing 8b (even though its 10b) is probably an issue with BD. Could be MacOS though.
"About the VRR support, I learned from the team that we may introduce it in an upgraded chipset in the future, but it’s not likely that we can implement it in the VMM7100 chipset."
So it seems our speculation is likely correct. Also, BD showing 8b (even though its 10b) is probably an issue with BD. Could be MacOS though.
I have also experienced this. I was hoping to just be able to do clamshell mode but it downgrades the output quite a bit for some reason.
Update on this post.
After plugging it into my intel macbook, and back to my m1 macbook pro, and going from YCBCR to RGB, I don't believe I'm getting 4:4:4 sampling anymore. The text looks very bad compared to how it was before. How do I check what subsampling I'm getting from the LG C2?
Is 4:4:4 controlled via MacOS or some setting in the TV?
I think I will remove the BLK from the OP until some other guys confirm that it works correctly. U have to press the green button 5 times fast
Getting full visible 4:4:4 or RGB requires setting the input icon to PC on LG OLEDs.
Does the VMM7100 also have wake issues like the VMM6100? I tried a lot of betterdisplay settings but I still get no signal until i reconnect the adapter while my macbook is open quite often.
Thanks for this! I'm on a Mac Studio, but not using a doc. Is there a solution for usb-c/thunderbolt to hdmi 2.1 now or do I have to use a dock that has dp 1.4?
For thunderbolt to HDMI 2.1 directly, use the method from the fist post on this thread with this adapter.
https://www.amazon.com/Cable-Matter...62961&sprefix=usb+c+to+hdmi+2.1,aps,94&sr=8-9