Last question. Did you look at the usb c prioritisation setting in the monitor? If it’s set to high resolution it may work.
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2020 MacBook Pro 8th Gen with 2 4K displays
- Thread starter citivolus
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It would shock and astound me if a 2020 MacBook Pro couldn’t power 4K displays properly. Seems we have some here saying it won’t work well at all and others saying it works perfectly. I dunno what to believe. 
For all of my use cases, I don't... I only want monitor signal over the cable. I don't use fancy monitors with built in hubs though, and if they do have a built in hub that I want to use, I have used a separate USB cable from my TS3+ dock... but typically just use the dock for any other USB devices. Typically I want all the bandwidth going to the monitor to be signal-related only as I use 4K external monitors exclusively.
This is true.
Looking into this a little deeper, you can actually get thunderbolt monitors. Hence why the 8th gen can power a 5k. But if relying on DP 1.2, this cant display 5k. Only has bandwidth for 1 4K monitor per port 2 60 hz. I can see why people get bad results most likely due to connectivity issues.
Yes I did--setting it to high resolution was the only way I could get 60Hz at 1080p, at the cost of dropping the speed of the USB hub to 2.0.
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I totally agree--that's why I initially ordered the 8th Gen, and have ended up also buying the 10th Gen and spent so much time testing this. I think the rub here is that I want to connect those 4K displays over native USB-C so I can also get PD and data connectivity for other devices (ethernet and webcam). Maybe there's another way to do this via USB-C to DisplayPort but that wouldn't meet my particular needs.
Maybe we can put this to bed this way: has anyone been able to connect an 8th Gen to a 4K display @ 60Hz with a resolution greater than 1080P and HiDPI enabled? If so, what connection method are you using?Seems we have some here saying it won’t work well at all and others saying it works perfectly. I dunno what to believe.
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Yes. a 2018 13" MacBook Pro with i5-8259U using an Accell USB-C to DisplayPort 1.2 supporting "DisplayPort Alternate Mode" connected to a Dell P2415Q monitor. Running 3840x2160 @ 60Hz. It performed perfectly. It only handled monitor signal, no other USB functionality and no charging.
The cable I used is here: https://www.amazon.com/gp/product/B01CKJPTOU/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
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On the dell forum it confirms that there is bandwidth for 4K and usb 2 data for hbr2. Have you looked at the shift and command option you need to perform in the display settings on the Mac?
Yes...the instructions describe a process to enable additional resolutions with a "Low Resolution" feature which seems to disable HiDPI (Apple's retina/pixel doubling feature). I tried it and it is very blurry
Blurry on the built in screen? You need 3 screens?Yes...the instructions describe a process to enable additional resolutions with a "Low Resolution" feature which seems to disable HiDPI (Apple's retina/pixel doubling feature). I tried it and it is very blurry
I'm going to try using a Thunderbolt 3 dock. I've ordered this CalDigit Mini Dock and will check it out when it arrives next week.
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I need two external screens and am running the MBP in clamshell mode.
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Blurry on the external monitors; that's why it is called "Low Resolution".
I need two external screens and am running the MBP in clamshell mode.
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i wouldn’t run the displays scaled at 1440p, as its a non integer scale of 2160p. When you choose a desktop resolution thats a non integer scale of the displays resolution, it requires your computer to render everything at a higher resolution and then downscale it, which almost certainly impacts performance. But that’s not the biggest reason to me. I had that 2015 macbook pro i owned set to 1680 x 1050 for the whole time i owned it, because I did like the extra space. But then I switched it off 1680 x 1050 and i realized that u lose almost all of the benefit of the 2560 x 1600 retina display at that reaolution. This is becuase that downscaling process introduces a lot of blur to everything on screen. This is a good article on it, just skip a few paragraphs in to the paragraph thats starts at “The Display pane”.
Mac external displays for designers and developers
If you’re considering an external display for your Mac, there’s a few important decisions to make. Apple doesn’t sell external displays any more, so you can’t just default to their wisdom. That’s an issue, because not all displays are well suited for Macs.
1080p scaled may be kinda big, but i think its important to skip all the fuzzy scaling sizes and select the proper integer one for the 4k displays
Yes...the instructions describe a process to enable additional resolutions with a "Low Resolution" feature which seems to disable HiDPI (Apple's retina/pixel doubling feature). I tried it and it is very blurry
Have you turned on High Data Prioritization in the Dell monitor OSD? I get 4K@60hz with USB 3 all over USB-C on a 10th gen and 8th gen/2019 MBP 13. There's a weird bug where it selects 30hz instead of 60hz. Just hit Ctrl when selecting Scaled and tick the box to enable low resolutions. Don't pick a low resolution, just change your refresh rate here.
Thanks but I think 1080p would be just too big for me...i wouldn’t run the displays scaled at 1440p, as its a non integer scale of 2160p. When you choose a desktop resolution thats a non integer scale of the displays resolution, it requires your computer to render everything at a higher resolution and then downscale it, which almost certainly impacts performance. But that’s not the biggest reason to me. I had that 2015 macbook pro i owned set to 1680 x 1050 for the whole time i owned it, because I did like the extra space. But then I switched it off 1680 x 1050 and i realized that u lose almost all of the benefit of the 2560 x 1600 retina display at that reaolution. This is becuase that downscaling process introduces a lot of blur to everything on screen. This is a good article on it, just skip a few paragraphs in to the paragraph thats starts at “The Display pane”.
Mac external displays for designers and developers
If you’re considering an external display for your Mac, there’s a few important decisions to make. Apple doesn’t sell external displays any more, so you can’t just default to their wisdom. That’s an issue, because not all displays are well suited for Macs.bjango.com
1080p scaled may be kinda big, but i think its important to skip all the fuzzy scaling sizes and select the proper integer one for the 4k displays
In the end I decided that the 8th Gen just wasn't up to snuff for my needs so I sent it back today. Good news is that the 10th Gen does everything I need and will be a keeper!
This is Cable related.You need a ThunderBolt 3 Certified.
(Not claiming to be just USB C)
40Gbps 100W Thunderbolt 3 USB C to USB C Cable.
For me 4K is working seamlessly @ 60Hz.
You need to also set to resolution priority for USB C in the monitor settings.
HDR+ / HDR400 works for me perfectly too.
Using Lunar to sync brightness / contrast: https://lunar.fyi
Take a look at this image:
(Not claiming to be just USB C)
40Gbps 100W Thunderbolt 3 USB C to USB C Cable.
For me 4K is working seamlessly @ 60Hz.
You need to also set to resolution priority for USB C in the monitor settings.
HDR+ / HDR400 works for me perfectly too.
Using Lunar to sync brightness / contrast: https://lunar.fyi
Take a look at this image:
Sorry I’m new here - I wanted to clarify to wrap things up as I’ve been looking everywhere and havent found a conclusive answer:
Has anyone been able to run two external monitors on extended display (non-mirror) @4k 60Hz on a 13 inch macbook pro (10th gen/older)?
I know caldigit has the dock for it but wondering how well it actually runs on those specs? And if possible theres a cheaper alternative (USB-C to display port + USB-C to HDMI with charging hub)?
thank you!