USB C with MacBook Pro

Lol, yes @framerate - works = 4K@60Hz.

@NZgeek, @Techmo -
And yes. the Apple TB3 USB-C (0.8M) cable is working. It is supporting the following -
Display at 4K@60Hz; Keyboard, Mouse and LAN via the USBC Hub on the back of the monitor. So, for now, I have a true one-cable solution. When I get my second Spectrum, I will then have a two-cable solution. I just need to find a longer TB3 USB-C cable that supports display.

This Belkin F2CD085ds2M-BLK that did not work between the MacBook Pro and the Spectrum worked for a Dell G3 USB-C Gaming Laptop, albeit at less than 30 Hz. So, somehow this Belkin is not compatible with a Mac :(.
I have now ordered a Cable Matters 6.6’ active cable that @Anverild has suggested and it is coming in on Wednesday. I’ll update this post.
Apple’s 0.8m works fine at 60Hz.

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I just got the CableMatters 6.6’ TB4 USB-C and it works with the MacBook Pro at 60Hz.

Sorry folks, I’m highly confused. What cable do I need to get the new Macbook Pro 2021 working with 120Hz @ 4k now? USB-C to USB-C Thunderbolt cable, or USB-C (Macbook) to DisplayPort (Spectrum)?

It depends on whether using a single cable for both power and video is important to you.

If it’s not, go for the USB-C to DP cable. The USB-C input on the Spectrum has a few known issues (such as not supporting DSC yet) which means it’s a bit more limited in what video signals it can handle. The DP input doesn’t have these issues.

If a single cable is desirable and you don’t mind waiting for the various issues to get fixed, I’d recommend getting a Thunderbolt 4 cable. You can guarantee that a TB4 cable is able to carry a DP signal, which is not the case with TB3 or other USB-C cables.

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Thanks a lot for your answer @NZgeek - I guess I’ll go for the DisplayPort to USB-C cable then.

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I am only able to get 30hz with USB-C in clamshell mode. Any advice. This is the cable I am using.

I have managed to fix it, I had to go to Display settings and hit “Resolution: Default for display”. Immediately the display switched to 60Hz. Then I could reapply my Scaled text size setting and 60Hz remained.

Just incase someone else has the same issue.

I used usb-c cable with Spectrum and my macbook pro. But new Display Port cable just arrived. I tried and it works pretty well with 144Hz, usb-c only 60Hz. My current resolution is 3840x2160.

Firmware version 104
Select input source: DisplayPort

I have another issue. DP can not power my macbook. So I plugged-in also usb-c cable. But now, mac thinks that I have two external monitors. Any ideas how can I fix it please?

usb-c cable: original eve usb-c cable
DisplayPort cable:

I can’t say much about why you’re not getting 144Hz with the USB-C to DP cable. You should be able to get the full 144Hz, so long as your MacBook is capable of it. Not all models are, especially if yours is from 2017 or earlier.

As for the multiple monitors, that makes perfect sense. You’ve got 2 active video connections: the USB-C cable itself, and the USB-C to DP cable. I’m not an expert on Mac OS so I don’t know what you have to do to make the OS ignore one of the monitor connections.

Its not a perfect solution, but you can set your “third monitor” to mirror image from one of yours real monitors. As a result your GPU will compute only two monitors output but transmit copy of your primary monitor image through USB-C. For you it will look like your OS have just two screens.

Any luck with reaching out to Apple Support?

Hi @quatermain,

Instead of using the USB C port on the bottom of the Spectrum, use the one on the side? but the problem with that is, you will always have to switch to the bottom port when upgrading firmware.

I will bring this to the Team to look for a permanent solution.

That likely won’t work as the side USB port only outputs 15W power delivery, vs 100W for the bottom port. It’ll charge the Mac but only very slowly, and battery may still go down over the course of the day.

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I guess the only way to solve this problem is to get the USB-C working then😂

@quatermain - what MacBook do you own?

thanks for answers.

I have MacBook Pro (14-inch, 2021) Apple M1 Pro.

I tried side usb-c, it doesn’t work.

I will try that mirror hack, this tool SwitchResX should help. I will try it tomorrow.

Any ETA on when a firmware will be released that supports DSC?

People have reported 144Hz working via USB-C on firmware 105, so I can only assume that DSC has finally been enabled.

However, it still only seems to work on M1 Macs. It’s definitely not working for me on an Intel-based MBP on Monterey 12.1.

Hi @quatermain,

Side USB-C is no longer an option as it would not be able to charge your Macbook throughout the day.

Are you running on macOS Monterey?

Also, are you willing to do an upgrade to 105? as Jamie has mentioned, there have been reports of users being able to get 144hz after the update. However, most of the users were using TB3/4 cable.

yes, Monterey. Where can I download 105?

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