Hi, I just got a Samsung QN90D 43", and while I could get 4k 144hz 4:4:4 on my M4 MB Pro on Sequoia, on my Mac Studio M2 Max on Sonoma I can't go above 60hz without 4:4:4 turning off automatically.
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DP/USB-C/Thunderbolt to HDMI 2.1 4k@120hz RGB4:4:4 10b HDR with Apple Silicon M1-M4 now possible !
- Thread starter Zorast
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Hello i have this oneugreen adapter, , i checked the fm version and its having the compatible chip, is there some firmware that can be compatible with this ugreen cable?
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I have an M4 Max in a Mac Studio running this same monitor, but I think the M4 Pro MBP has the same capabilities. You don’t have to run it as two monitors, you can get the full resolution (7680x2160) at 120Hz using a quality USB-C to DP 2.0 cable and software like BetterDisplay to allow more resolutions and refresh rates. Over HDMI, I was only able to get 7680x2160@60Hz.
Be sure your monitor is on the newest firmware (currently 1007) and set to DP 2.0 mode (I think default is DP 1.4).
Hi, I got an MBP M4 Max and LG 38GN950, connected through Belkin DP1.4 -> Thunderbolt
Just switched from MBP M1 Max, which had zero problems running this monitor in native 3840x1600, HiRes, 120Hz, 10bit 4:4:4 (with the help of BetterDisplay, no hdr), on MacOS Sequoia 15.5
For the life of me, I'm not able to replicate it on M4 - whichever combination of settings I select, enabling HiRes always kicks me back to 3360x1400. The flexible scaling is enabled.
Tried about everything in this thread that doesn't involve hardware change. Downgrading refresh rate, also with Shift key to show the fractional ones doesn't work.
In the M1 max, I could select 3816x1590 in macos settings, enable HiRes in BD, then up the resolution to native in BD.
On M4, I don't have the 3816x1590 at all, adding this in Custom Scaled resolutions doesn't enable it in native macos settings, selecting it in BD is either/or with HiRes just like the rest of resolutions higher than 3360x1400
Is there anything I can try or is it just not possible?
Just switched from MBP M1 Max, which had zero problems running this monitor in native 3840x1600, HiRes, 120Hz, 10bit 4:4:4 (with the help of BetterDisplay, no hdr), on MacOS Sequoia 15.5
For the life of me, I'm not able to replicate it on M4 - whichever combination of settings I select, enabling HiRes always kicks me back to 3360x1400. The flexible scaling is enabled.
Tried about everything in this thread that doesn't involve hardware change. Downgrading refresh rate, also with Shift key to show the fractional ones doesn't work.
In the M1 max, I could select 3816x1590 in macos settings, enable HiRes in BD, then up the resolution to native in BD.
On M4, I don't have the 3816x1590 at all, adding this in Custom Scaled resolutions doesn't enable it in native macos settings, selecting it in BD is either/or with HiRes just like the rest of resolutions higher than 3360x1400
Is there anything I can try or is it just not possible?
Had to revert to the original firmware today. My secondary portrait screen had an ‘ant’ screen every time the Mac mini woke up from sleep or cold boot. I had to change the source constantly to get a proper display. It was annoying, not even a specific screen like the LG C3, just a simple gaming 144Hz 2K screen.
Downloaded the latest firmware updater and used it first.
Spyder_fw_USBC_CM_MBP4k120.fullrom, but that one was basically installed the same as mentioned above…thought that they might have updated
Then I tried the: Spyder_fw_USBC_CM_7.02.112_MacOS 4K120Hz only.fullrom
I think this one is one of the OG firmware versions I used to use at the beginning with my M1 MBP.
Anyway now I'm at:
Firmware name: *der_fw_USBC_CM
Firmware version: 7.02.112
Configuration file version: 0x040
Did not test it on my C3, as it's working just fine in the Mac minis with the built-in HDMI port.
Thought that I would share, maybe some are running into the same issues.
Did anyone test macOS 26 ?
@waydabber says that macOS 26 work fine like before, nothing changes for us here in case of 4k@120hz
@waydabber says that macOS 26 work fine like before, nothing changes for us here in case of 4k@120hz
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I've tried literally everything to update this cable without success.
Unfortunately I dont have access to a Windows device with USB-C display alt, none of my colleagues or friends has one (its not common on most of the laptops sold here in Brazil, which are usually budget models).
I tried virtualization on macOS with UTM + Windows 11 without success, tried two methods: one using the downloaded VMMTool from cablemmaters site and other using one app at the Microsoft Store, both fail due to "GPU Initialization". The USB is being passed through apparently and I enable it on UTM taskbar, but it doesnt work, tried multiple times, on the UTM taskbar it shows USB 2.0 Billboard, something like this, maybe it should show other name? I believe it must some kind of problem related to the VM not understading or passing the adapter info correctly.
I also tried the "new" macOS compatible firmware injection tool that cablematters provides, it simply does not open on macOS 26... I checked all permissions, ran with sudo command, etc. does not open at all.
I'm running out of options, spent good money on this adapter (imported from amazon US because you cant find it easiliy in my country, cablematters model) just to get 120hz from my Macbook Air M1 to my LG OLED but cant flash the firmware, I own a desktop PC with windows and the macbook, usb-c display alt is a pain in the ass to get on a desktop pc (have to buy expensive TB4 pci-e card, etc.)
In the end my only option is to buy a windows pc with usb-c DP and return it after flashing the adapter, didnt want to do that because I get a little scared about having problems with the return, etc., and its a lot of money.... but in the end I believe this is what I will do, try to get from a store with a good return policy (like amazon) and return the next day...
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I'm starting to believe it's just not possible. I have a bug open with Apple on this because I have an M3 MBP and and M4 MBP so I can do same display & settings, and just swap the cable between them. No dice.
HiDPI / scaled displays don't support HDR on the M4 and M4 Pro UNLESS the scaled resolution is 4k or lower. So 1080p HiDPI (4k, 1080p x 2) works, but the 1440p I would guess most people would want to use, does not.
But it does on the M1, M2, and M3
😐
Still the same here on 26 RC.
Does anyone from CableMatters actively browse these forums? The app simply refuses to run and it doesn’t look like a permission issue, more like a fault in the actual exe.
Using a Windows PC is not an option for me. Also shouldn’t need to, just saying. I have a gaming PC but even most GPUs these days only come with DP and HDMI.
If we are talking about being able to get 4k@120 hz full RGB, I agree with Waydabber. I have been using Tahoe since the first public beta.