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 !

[carnafillian113]

I just flashed my VMM7100 adapter and now it won't output to a display from either my pc or my Mac. It now doesn't even register when I start up the flash program. It says it can't find it. The only instruction I didn't follow was I didn't plug in my laptop's power cable when I did it. I figured it wouldn't make a difference since I knew I had plenty of battery.

Is there anything I can do to fix this? Anything I can try? Or is it just fried

 

[Zorast]

RE: M2 HiDPI HDR 120Hz

According to this YouTuber:

Seems like on M2 you can't get HiDPI at 1440 or above with HDR and 120Hz together. It was an option in early Mac OS but no longer in the latest one.

M2 has an native HDMI 2.1 Port

 

[Kaszebe]

I have an M2 Mac Mini and am temporarily repurposing my LG C2 OLED 42" as a monitor (have a LG 34BK95U-W on order that should be delivered next week). I'm using BetterDisplay (no clue if I have it set up properly). When I try to change the refresh rate to 120hz, the text on the screen gets blurry (even moreso than normal using this monitor).

Does anyone know why? I have not created a "dummy" screen in BetterDisplay because I was unable to find a guide online and couldn't figure it out by myself.

And do you think will I be disappointed with the colors/resolution of the LG 34BK95U-W (it's a 5k2k monitor) compared to the LG C2 OLED?

 

[luaninuyasha]

Hello everyone. I currently have a VM1700 chip adapter in this link https://vi.aliexpress.com/item/1005004962095579.html (because I can't buy from Amazon in my country). But after flashing the type-c to HDMI firmware, I got 120hz option in display setting. But the problem is that when I choose 100 or 120hz, my LG C2 just cannot receive signal from Macbook Pro M1 anymore until I changed to 60hz again. While not having signal, my Macbook still recognize the display. Anybody have same issue? Please help me. Many thanks!

 

[komuh]

I have an M2 Mac Mini and am temporarily repurposing my LG C2 OLED 42" as a monitor (have a LG 34BK95U-W on order that should be delivered next week). I'm using BetterDisplay (no clue if I have it set up properly). When I try to change the refresh rate to 120hz, the text on the screen gets blurry (even moreso than normal using this monitor).

Does anyone know why? I have not created a "dummy" screen in BetterDisplay because I was unable to find a guide online and couldn't figure it out by myself.

And do you think will I be disappointed with the colors/resolution of the LG 34BK95U-W (it's a 5k2k monitor) compared to the LG C2 OLED?

It looks like output isn't RGB and it's going to be ycbcr420 or smth similar.

You can check it by pressing green button multiple time which will show you "debug" screen with info about resolution, refresh rate and output format.

To fix it you have to or flash your hdmi-usbc adapter with proper software and later change EDID more about that in https://forums.macrumors.com/thread...ith-apple-silicon-m1-m2-now-possible.2381664/ or if you are using HDMI and version is 2.1 you should make sure cable is working fine on other device.

 

[Zorast]

There is no other Firmware, the one linked in the OP is up to date.

 

[zucram]

I'm trying to figure out what adapter to buy in Sweden. Amazon is very different from country to country. Seems amazon.se only has the VMM6100. There's also the Anker one but this one looks the same but says 60hz and not 120hz. Can anyone confirm if it will work? Or does anyone know where one can buy the VMM7100 in Sweden? Trying to avoid huge shipping costs.

 

[ktravelet]

I have an M2 Mac Mini and am temporarily repurposing my LG C2 OLED 42" as a monitor (have a LG 34BK95U-W on order that should be delivered next week). I'm using BetterDisplay (no clue if I have it set up properly). When I try to change the refresh rate to 120hz, the text on the screen gets blurry (even moreso than normal using this monitor).

Does anyone know why? I have not created a "dummy" screen in BetterDisplay because I was unable to find a guide online and couldn't figure it out by myself.

And do you think will I be disappointed with the colors/resolution of the LG 34BK95U-W (it's a 5k2k monitor) compared to the LG C2 OLED?

Ditto to blurry fonts. I’m using a thunderbolt KVM with a DP monitor output with the cablematters DP -> HDMI adapter. Before the flash, everything was crystal clear but at 60hz, after the flash I can get 120hz but fonts are “jagged” and hard to read.

I tried turning off font smoothing via terminal (then restarting) and that didn’t seem to help. I’m not sure what else to try. Since this is VMM7100, I don’t have to mess with the EDID.

 

[kooki2]

+1 for working VMM7100 !

Would anyone be kind enough to send a FW that would potentially work for the VMM6212/VMM6210 ?

Appreciate you guys and thanks for the awesome tips so far.

Quick Edit :

I was able to make my little HUB work properly with the VMM6210 chip, giving me 10 bits 4:4:4 and 4k 120hz on my LG C1 48 inches.

Cheers!

Hello
May i ask how did you get to work VMM6210 support 10bit 4k 120hz??

 

[ktravelet]

Ditto to blurry fonts. I’m using a thunderbolt KVM with a DP monitor output with the cablematters DP -> HDMI adapter. Before the flash, everything was crystal clear but at 60hz, after the flash I can get 120hz but fonts are “jagged” and hard to read.

I tried turning off font smoothing via terminal (then restarting) and that didn’t seem to help. I’m not sure what else to try. Since this is VMM7100, I don’t have to mess with the EDID.

Follow up here. When I set the refresh rate to 60 hertz everything clears up. Something is not working for me at 120hz.

 

[ktravelet]

Another follow up, sorry for spamming. My windows machine also looks jagged with 120hz but clears up with 60hz.

I'm using this usb-c KVM switch linked below to switch between my Surface Laptop 7, and M1 pro Macbook Pro. I'm using all 48GBps certified usb-c cables, the Cable Matters DP -> HDMI adapter and a HDMI 2.1 certified cable to 43" Sony Bravia X85k tv.

usb-c KVM switch:

Vowish USB C KVM Switch 8K@60Hz 4K@120Hz, 2 Port Type C KVM Switch for 2 Computers Share 1 Monitor, USB C KCM with 3 USB 2.0 Ports & 100W Power Delivery, 2 USB-C Cables Included

usb type c kvm switch

www.amazon.com

 

[clutchm3]

In my experience, keeping the adapter connected DOES fix this issue of the TV switching off of PC mode, no dock used here. However, you'll have a new issue of your machine not wanting to wake from sleep sometimes (have to disconnect and reconnect the adapter to the Mac). Doesn't happen very often, and I'd say it's less annoying than fumbling with the LG menus to get back to PC mode.

I'm not using HDR though so can't comment on that.

You mean keeping adapter connected to the HDMI only? Not the Macbook itself? If so which adapter?

 

[dinosauradventure]

You mean keeping adapter connected to the HDMI only? Not the Macbook itself? If so which adapter?

Yes, keeping it connected to the HDMI cable keeps the input in PC mode. Adapter is the CableMatters VMM7100 linked in the OP.

 

[carnafillian113]

I just flashed my VMM7100 adapter and now it won't output to a display from either my pc or my Mac. It now doesn't even register when I start up the flash program. It says it can't find it. The only instruction I didn't follow was I didn't plug in my laptop's power cable when I did it. I figured it wouldn't make a difference since I knew I had plenty of battery.

Is there anything I can do to fix this? Anything I can try? Or is it just fried

Replying to myself here. I just bought ANOTHER one of these, tried it again, followed the instructions exactly, and bricked it again. 2/2 this solution does not work. I'm done with this.

 

[zakarhino]

Worked perfectly, no discernible difference between this solution and the previous USB-C to DisplayPort cable solution I was using. Now my PC can use DisplayPort (for GSYNC) and my Mac can use HDMI at 4k 120hz!

For reference I bought the Anker USB-C to HDMI adapter as linked in the OP.

 

[MakaniKai]

This is incredible and has totally saved my purchase decisions.

One thing I am running into that I am curious if anyone else is experiencing: intermittent and random few second black screens where it seems the connection is lost between my Sony A90K and the Mac studio. Using the cable matters VMM7100.

Did you find a fix for this? Mine is doing the same thing with a TS4 dock, MBP 14” M2 Max, and Odyssey Ark screen. Same adapter.

 

[clutchm3]

Yes, keeping it connected to the HDMI cable keeps the input in PC mode. Adapter is the CableMatters VMM7100 linked in the OP.

This does not work as confirmed by others. Once the cable is disconnected from the LG C2, the PC Icon setting gets reset as always. So this won't solve that specific problem.

Also no VRR/Gsync support from what I understand?

 

[clutchm3]

RE: M2 HiDPI HDR 120Hz

According to this YouTuber:

Seems like on M2 you can't get HiDPI at 1440 or above with HDR and 120Hz together. It was an option in early Mac OS but no longer in the latest one.

Also, I have an M2 Max 16" and Directly plugging into the HDMI I get 4K/120 with VRR. Resolution at 3840 x 2160 getting HDR just fine. So I think this video is outdated.

The only thing I need to fix is PC mode being reset on my LG C2 every time the HDMI cable is unplugged. From my research this adapter does not fix that issue and also will lose VRR. For future M2 Max readers.

 

[chargerinthebox]

So has anyone gotten HDR to work on 4k@120hz, 10b, 4:4:4 (full RGB)? I have to turn the refresh rate to 60hz to get the HDR toggle.

 

[bigroundapple]

Replying to myself here. I just bought ANOTHER one of these, tried it again, followed the instructions exactly, and bricked it again. 2/2 this solution does not work. I'm done with this.

I have the same issue. Bought the Cable Matters adapter and the Anker adapter the 2nd time and the instructions bricked both.

I was able to get the adapter to work by installing this firmware however it only displays at 4k60hz

Cable Matters Knowledge Base - Page not found

Knowledge Base for Cable Matters Connectivity Products

kb.cablematters.com

 

[Zorast]

@ All

U can disable hibernate when lid is closed and connected to power cable to prevent some wake up issues with the adapter.

 

[Zorast]

So has anyone gotten HDR to work on 4k@120hz, 10b, 4:4:4 (full RGB)? I have to turn the refresh rate to 60hz to get the HDR toggle.

HDR works perfekt in 4:4:4 and 120hz 4k

 

[Zorast]

Also, I have an M2 Max 16" and Directly plugging into the HDMI I get 4K/120 with VRR. Resolution at 3840 x 2160 getting HDR just fine. So I think this video is outdated.

The only thing I need to fix is PC mode being reset on my LG C2 every time the HDMI cable is unplugged. From my research this adapter does not fix that issue and also will lose VRR. For future M2 Max readers.

When the adapter is still connected to the HDMI cable and an external powered hub/dock it works. But vrr will not.

 

[chargerinthebox]

HDR works perfekt in 4:4:4 and 120hz 4k

Sadly, does not work for me on VMM6100. I did modify the EDID for transportation over DP. Do i need to tweak anything else? I tried the firmware you posted in the other thread too but no luck. Additionally, the usb port stops working with that firmware.

 

[Zorast]

U have to use Adapter that we verified and HDMI 2.1 certified cable to be 100% safe that it work.