DP/USB-C/Thunderbolt to HDMI 2.1 4k@120hz RGB4:4:4 10b HDR with Apple Silicon M1-M4 now possible !

[5bjoshua]

Have been using a LG OLED C4 as a monitor and wanted to create a bit more of an elegant solution so grabbed a 201428 adapter. HDMI with USB-C PD.

Loaded a different firmware onto it via boot camp on an old intel based Mac as parallels wouldn't work and now have it working 4k120hz with HDR.

One thing did get used to was I could use adaptive sync when using HDMI straight into the MacBook Pro and adjust the brightness (only when HDR is enabled). Now these don't work! Wondering whether it's a limitation of USB-C or the adapter firmware? EDIT - Re-enabled HDR and the brightness control work again... RGB 12b 4L12 HDR10

Anyone been able to get an adapter that has working Adaptive Sync?

My MacBook Pro M3 Max has HDMI 2.1 but just wanted a more elegant solution of plugging the laptop in when I am at home instead of unplugging the HDMI cable all the time.

 

[waydabber]

@Zorast - can you try the latest BetterDisplay interim pre-release?

So the procedure should be the following:

• Switch to 60Hz
• Select some HiDPI resolution that is not available normally with 120Hz but otherwise is available at 1920x1080 HiDPI or 3840x2160 HiDPI (like 120Hz on the M1 Pro)
• Switch to 120Hz in the "unexposed" refresh rate list
• Enable Configuration Protection > Refresh Rate

The refresh rate configuration protection should kick in properly next time (for the given display layout where the above procedure was carried out before) and should switch to the unexposed 120Hz mode automatically.

(note for others: this tutorial is about allowing 120Hz - or other higher - refresh rates with HiDPI resolutions for which this is no longer available with recent macOS versions on some M1 Pro Macs - so it's a very niche issue, most are not affected by this).

 

[iambk]

Has nobody tried the new Cable Matters USB C to HDMI 2.1 Cable (201392)?

I got the older Cable Matters 48Gbps 8K USB C to HDMI 2.1 Cable (201362) and while it can do 3L6 mostly OK, it only works sometimes for higher modes like 3L8 or 4L8. I don't think I've ever gotten 4L10 out of it. I've tried multiple firmwares and even gotten the cable replaced.

Especially since it works better on some HDMI ports than others (all HDMI 2.1 ports, 3 different TVs), I suspect it just doesn't put out as clean of a signal as the adapter/dongle (201388) that everyone here talks about so much.

A dongle seems less than ideal, but if I need to order the dongle then I'll do that. Really curious to know if the new cable 201392 works as good or better than the dongle though.

I do have BetterDisplay. I've given up screwing with the 201362 cable, but BetterDisplay works well with the Dell HD22Q dock. Mostly reliable RGB 10b 4L10! No vm7100 reset option in BetterDisplay, since the Dell Dock doesn't have a vm7100. I has the VMM6211. If the vm7100 just a problematic chip? I have had to pull the cable from the computer a few times for the Dell dock but it's far more reliable than that CM 201392 cable.

One thing I don't understand. When I first used the Dell HD22Q dock, 12bit/DolbyVision showed up as options (although the colors where all messed up when I selected Dolby Vision). Now, DolbyVision doesn't ever show up as an option. I don't know if it's because the new version of BetterDisplay knows better. I'm really curious how BetterDisplay decides what modes are available.

I don't need DolbyVision. I don't even use HDR mode, although it is very effective with BetterDisplay at making my screen brighter.

I don't even know if I can tell a difference from 120Hz, but everyone here seems crazy about 120Hz so I'm trying to go with it. And I want a cable that can do full HDMI 2.1 bandwidth. I'll settle for the dongle if it'll work better than the new cable.

 

[Fais Has]

Hi everyone, I haven't updated my OS yet, 16" M3 MAX still on Sonoma 14.3.1 and my system attached to TS4 with cable matters model 201388-A connected to my LG C2. everything working sharp 4K,120,HDR 10 etc.

I think I'm going update to Sequoia latest version but I want to make sure with M3 MAX I will have 4K 120 HDR 10 On Sequoia?

I don't Have a second monitor, I use my laptop screen as second monitor and my LG C2 as main monitor

Thanks!

 

[Zacharybinx34]

Really nice @dinosauradventure, when using "other unexposed frequencies" 120hz I can reproduce 4K HiDPI. So confirm that this will work!

Steps:

1. BetterDisplay: Select 4k HiDPI @ 60hz

View attachment 2446583

2. BetterDisplay: Use 120hz on BetterDisplay "other unexposed frequencies"

View attachment 2443615

Info: BD config protection does not work correctly for now. It's better to disable it and then change every time to "unexposed frequencies" 120hz manually.


BUT: I warn u, apple will read this and "fix" this faster as u can see

Where do I find this in Better Displays?

 

[Zorast]

INFO for 4k HiDPI 120hz unexposed on macOS 15

@waydabber just released a new version of BetterDisplay that can handle 120Hz unexposed frequencies better. So when config protection is active, it remains active even after reconnecting or standby. We tested all possible cases together to get it working, so we hope it will also work for you!

It’s available with Version 3.1.3 Internal Pre-Release Build 35536 or newer. You can get this update when you enable pre-release/internal pre-release updates releases here:

A can find a complete how to here: Howto

 

[Zorast]

Where do I find this in Better Displays?

U can find a complete how to here: Howto

 

[abe17]

I got the same error and was able to fix it. But (and it is a HUGE BUT) it was not easy. The "short" version:

1. You need to have a laptop that supports DP alt mode over usbc. I used an older windows laptop that was able to show/mirror the laptop screen when connected to the TV via usbc. But the flash resulted in the error and effectively "bricked" the adapter as it would not connect/display. I ended up downloading Parallels Desktop on my M1 MBP and got it to work that way.

2. Use the cable matters knowledge board instructions, https://kb.cablematters.com/index.php?View=entry&EntryID=147

3. You need to be comfortable going in and modifying text files in the Firmware Update Tool. There is a table "VMM_Firmware_Table.txt" that effectively tells the application what firmware fullrom to apply (located in bin). I figured I can't break the adapter any more than it is already is so I went in and tried different combinations until it worked.

4. I was not expecting my trial/error to work so I don't have it documented. I do remember having to pick one of the older "fullroms" to get the adapter displaying again. Once I got to that point, I was able to follow the instructions at the above link and it worked. I'm 99% sure it installed the "Spyder_fw_DP_CM_MBP4k120.fullrom" version.

Sorry I can't be of more help than this.

Thank you so much dude, it works on me!

you really saved my life!

 

[Zacharybinx34]

A can find a complete how to here: Howto

1. BetterDisplay: Select 4k HiDPI @ 60hz in Display Mode and be sure the HiDPI button is Blue

I'm not seeing this at all.

 

[Fais Has]

please, Can someone clear for me with M3 MAX this solution still working on sequoia?

 

[dnvjmh313]

1. BetterDisplay: Select 4k HiDPI @ 60hz in Display Mode and be sure the HiDPI button is Blue

I'm not seeing this at all.

Same here, the maximum resolution under 60Hz HiDPI is 3072x1728, and 4K is not available.

 

[waydabber]

This trick will only work for 4K@120Hz displays using connections where you have 3840x2160 HiDPI available at 60Hz and 3840x2160 LoDPI at 120Hz.

 

[dnvjmh313]

This trick will only work for 4K@120Hz displays using connections where you have 3840x2160 HiDPI available at 60Hz and 3840x2160 LoDPI at 120Hz.

Using a Mac mini M2 and LG C2 with macOS 15.1, so it doesn’t work, right? HiDPI is not available at 4K 60Hz.

 

[Zorast]

Using a Mac mini M2 and LG C2 with macOS 15.1, so it doesn’t work, right? HiDPI is not available at 4K 60Hz.

Also to @Zacharybinx34

Do u have an EDID override for DP-Transportstream enabled or an Adapter with special Firmware?

What's the max resolution u see with HiDPI possible @ 60hz ? U can enable this option in BetterDisplay to get better results:

 

[Zorast]

please, Can someone clear for me with M3 MAX this solution still working on sequoia?

yes it will, but on a M3 u have an native HDMI 2.1 Port

 

[dnvjmh313]

Also to @Zacharybinx34

Do u have an EDID override for DP-Transportstream enabled or an Adapter with special Firmware?

What's the max resolution u see with HiDPI possible @ 60hz ? U can enable this option in BetterDisplay to get better results:

View attachment 2454163

I’m using the Anker 518 USB-c adaptor(8khdmi). After flashing the firmware mentioned in the article, the maximum resolution at 60Hz with HiDPI is 3072×1638.With both HiDPI and HDR enabled, the maximum resolution is 2432×1368,flexible scaling is already enabled.The maximum resolution at 120Hz HiDPI is also 3072 x 1728.

 

[Zacharybinx34]

Also to @Zacharybinx34

Do u have an EDID override for DP-Transportstream enabled or an Adapter with special Firmware?

What's the max resolution u see with HiDPI possible @ 60hz ? U can enable this option in BetterDisplay to get better results:

View attachment 2454163

Yes, but I'm not seeing where to change the resolution at all like in the screenshots in this app.

I have the modded firmware on the VMM7100.

 

[ashepp]

Has anyone encountered wireless charging issues with the Dell HD22Q dock? I have 3840x2160 @120hz working great with displayport dongle, better display and firmware update but my Samsung fold 6 refuses to wirelessly charge on the dock (get orange flashing led) after a short few seconds power draw. I do have a thinborne case on the fold and temps do rise which I thought was the issue, but it also seems to have below 30 degrees when I have a fan blowing on the setup. Appreciate any ideas ? Could a firmware change on dock or somehow reducing the charging wattage work?

 

[Zorast]

I’m using the Anker 518 USB-c adaptor(8khdmi). After flashing the firmware mentioned in the article, the maximum resolution at 60Hz with HiDPI is 3072×1638.With both HiDPI and HDR enabled, the maximum resolution is 2432×1368,flexible scaling is already enabled.The maximum resolution at 120Hz HiDPI is also 3072 x 1728.


View attachment 2454216

Also for u @Zacharybinx34

Read the OP plz.... U have to disable HDR this does not work since macOS 14.1 !!

I update the macOS 15 HiDPI HowTo with this information too: HowTo

 

[Zacharybinx34]

Also for u @Zacharybinx34

Read the OP plz.... U have to disable HDR this does not work since macOS 14.1 !!

I update the macOS 15 HiDPI HowTo with this information too: HowTo

Disable it on my TV?

Then what do I need to change with BetterDisplay?

I cannot find this screen in Better Display - where is it?

 

[psyguy]

Has anyone encountered wireless charging issues with the Dell HD22Q dock? I have 3840x2160 @120hz working great with displayport dongle, better display and firmware update but my Samsung fold 6 refuses to wirelessly charge on the dock (get orange flashing led) after a short few seconds power draw. I do have a thinborne case on the fold and temps do rise which I thought was the issue, but it also seems to have below 30 degrees when I have a fan blowing on the setup. Appreciate any ideas ? Could a firmware change on dock or somehow reducing the charging wattage work?

The wireless charging is finicky on it as is, especially dependent on the power draw and the placement not being EXACT.

That being said, when you say "firmware update", do you mean you updated the firmware on the dock? It's supposed to work out of the box with an EDID profile right through the HDMI.

 

[ashepp]

The wireless charging is finicky on it as is, especially dependent on the power draw and the placement not being EXACT.

That being said, when you say "firmware update", do you mean you updated the firmware on the dock? It's supposed to work out of the box with an EDID profile right through the HDMI.

I found the instructions a little cryptic and honestly, still not entirely sure specifically what I did to get it working, but I used the firmware from the start of the thread as HDMI did not work for me at 120Hz out of the box (a used ebay purchase) :

1.3.
DP>HDMI 2.1: VMM7100: (Plug&Play)
CableMatters 102101
Plz use Archive: CM Firmware 4k 120hz RGB VMM7100 ONLY DP to HDMI 2 1

I assumed it was because the HDMI port was not 2.1 capable and ended up using displayport which is working great. I'm a little hesitant to rock the boat at this point as things seem to be working (occasional millisecond scrambled screen which quickly resolves). But I'll take any additional instruction on what I should be doing as it was hard to parse from this thread.

 

[psyguy]

I found the instructions a little cryptic and honestly, still not entirely sure specifically what I did to get it working, but I used the firmware from the start of the thread as HDMI did not work for me at 120Hz out of the box (a used ebay purchase) :

1.3.
DP>HDMI 2.1: VMM7100: (Plug&Play)
CableMatters 102101
Plz use Archive: CM Firmware 4k 120hz RGB VMM7100 ONLY DP to HDMI 2 1

I assumed it was because the HDMI port was not 2.1 capable and ended up using displayport which is working great. I'm a little hesitant to rock the boat at this point as things seem to be working (occasional millisecond scrambled screen which quickly resolves). But I'll take any additional instruction on what I should be doing as it was hard to parse from this thread.

Well, if it's working well for you, just do as you see fit, though when I use the dock with HDMI, I don't have any issues, including no millisecond scramble.

I suspect the firmware you installed might've disabled the charging functionality or power handling to some extent. I haven't messed with it in a while, but I can probably extract the original firmware off mine if you didn't make a backup.

It's more of a matter of you bought more than you needed. Though to be fair, I also have that DP>HDMI and a whole other Dell TB24 thunderbolt dock that I actually swapped it out for cause I was tired of the phone dock being in the way.

Out of all the solutions, the Dell HD22Q is the most plug and play, zero adjustments after the EDID is running solutions of them all (you might occasionally have to relink the EDID on rare occasions).

---

Okay! You have a Dell HD22Q, an LG CX, and a Macbook Pro M3. Let's troubleshoot.

1. Can you tell me what firmware you have running on the Dell HD22Q? It should be version 6.05.000 and should look like this, when you plug it in directly to a Windows PC or Parallels (no dongle, just raw dog the HDMI or DP). If it's not 6.05, did you make a backup?
   
2. Did you make an EDID profile for your LG CX to work with this dock?
3. Can you charge any other device with the dock still?
4. Are you hydrated? Make sure to drink water and stretch once an hour for you wellbeing.

 

[Zorast]

Disable it on my TV?

Then what do I need to change with BetterDisplay?

I cannot find this screen in Better Display - where is it?

So now klick refresh rate and u will see unexposed frequencies at the bottom

 

[Zacharybinx34]

So now klick refresh rate and u will see unexposed frequencies at the bottom

Click it where exactly?