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Macs4u

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Original poster
Apr 19, 2008
387
352
Stoke on Trent
Hi,

I have an LG 27UK600 4k monitor that has display port and hdmi connections. Thinking of buying a used MacBook 12" early 2016 tomorrow. Will this connect and run at 4k? Can you get USBC to display port? As would need that wouldn't I?
[doublepost=1555785274][/doublepost]I've seen a cable that has USBC to display port and has power pass through so it will charge whilst docked. With the MacBook only having 1 port, could I get an adapter to make it 2 ports and connect everything to one which would leave me with 1 port to plug my portable SSD in?
 
Hi,

I know you can get adapters for the Macbook 12" such as.. https://www.amazon.co.uk/Satechi-Al...chi+macbook&qid=1555788383&s=computers&sr=1-4

BUT, i have a 4k monitor and i also need to plug in my portable ssd aswell as have it charging all at the same time.

So, is there anything similar to the above but does 4k to displayport so i can get 4k 60 aswell as a spare usb or 2 so i can plug in accessories?
[doublepost=1555788592][/doublepost]or could i use the above and then plug this below into the usbc port on the outside of the above and do it that way?

https://www.amazon.co.uk/CHOETECH-D...passthrough&qid=1555788535&s=computers&sr=1-3
 
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Yeah mine isnt the ultrafine
USB-C to DisplayPort or HDMI is not a problem. There are a few things you should be aware of though.

1) There are direct USB-C to DisplayPort and USB-C to HDMI cables, but they don't provide power to the MacBook.

2) If you want to use this for extended periods, you will need an external power source. Therefore you would need a USB-C to DisplayPort dongle or a USB-C to HDMI dongle with a USB-C power input.

3) If your cable or dongle is only for video, it means you can't plug anything else in. So, to plug in a drive for example, you'd have to unplug the video. However, you can get multifunction hubs that have USB ports.

3) In a USB-C multi-function hub, you cannot have 4Kp60 and USB 3 at the same time. You can have 4Kp60 alone, 4Kp60 with USB 2, or else 4Kp30 with USB 3. A lot of dongles will advertise 4K + USB 3, but if you read the fine print (assuming it even has fine print), it will be 4Kp30 + USB 3. Only a few dongles have 4Kp60 + USB 2, but of course if you go that route, your external SSD will be limited to USB 2 speeds.

4) A lot of the dongles and cables out there are flaky. Buyer beware.

I got two dongles. One is a multi-function hub with HDMI 4Kp30 plus USB 3 (as well as SD card reader and Gigabit Ethernet), and the other is a dedicated 4Kp60 HDMI adapter. Both have power inputs. It turns out I use neither though, since at home I have a 5K 27" iMac with another 2.5K 27" iMac used as a secondary monitor anyway. o_O
 
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So id be basically stuffed then. Either power or be able to plug my external ssd in.
You can do power input, 4Kp60 output, and SSD input all at the same time, but for the SSD you would be limited to USB 2 speeds only.

If you want USB 3 speeds for your SSD, you can only do video at up to 4Kp30 (which IMO is not sufficient).
 
As an aside, if you plan on using that setup (MacBook 12" + external 4K monitor) for more than just light web browsing and word processing, I'd suggest bumping up to the 2017 model. Better graphics is necessary for a smooth 4K experience.

Also, do be aware that only the most immediate 2x resolution (so from 3840x2160, you get 1920x1080) will perform "decently". Any other scaled resolution like 2560x1440 (effective 5120x2880) will make the MacBook come to a crawl due to the recent Mac OS version employing far too many full screen animations.

P.S.: oh, and I have that dock above. It does work with bus-powered USB SSD. I have a Samsung T5 and a WD SSD and both work just fine. Also, not sure if it's a behavior of Mojave or the dock, but if you're transferring files, you can just leave the screen static (so don't do anything), and transfer speeds will occasionally pull slightly ahead of USB 2.0 specs. Not up to USB 3.0, but at least it will speed up your transfer.
 
As an aside, if you plan on using that setup (MacBook 12" + external 4K monitor) for more than just light web browsing and word processing, I'd suggest bumping up to the 2017 model. Better graphics is necessary for a smooth 4K experience.

Also, do be aware that only the most immediate 2x resolution (so from 3840x2160, you get 1920x1080) will perform "decently". Any other scaled resolution like 2560x1440 (effective 5120x2880) will make the MacBook come to a crawl due to the recent Mac OS version employing far too many full screen animations.
Dunno about Mojave, but my 2017 MacBook drove an external 2560x1440 screen fine. Or are you talking about a 3840x2160 screen scaled down to a 2560x1440 resolution? I didn't actually test that.

P.S.: oh, and I have that dock above. It does work with bus-powered USB SSD. I have a Samsung T5 and a WD SSD and both work just fine. Also, not sure if it's a behavior of Mojave or the dock, but if you're transferring files, you can just leave the screen static (so don't do anything), and transfer speeds will occasionally pull slightly ahead of USB 2.0 specs. Not up to USB 3.0, but at least it will speed up your transfer.
Interesting. I wasn't aware of that.

And good to see that it can drive a Samsung T5. I have the T5 as well. Note though that the T5 is one of the lower power consumption units, as it maxes out at 3.5 Watts.
 
Dunno about Mojave, but my 2017 MacBook drove an external 2560x1440 screen fine. Or are you talking about a 3840x2160 screen scaled down to a 2560x1440 resolution? I didn't actually test that.

I'm talking about scaling 5120x2880 to a 3840x2160 screen. It's "effectively" scaling 5K to 4K. The 2016 MacBook will slow to a crawl with that. The 2017 is... passable.

Also if you are using a 2560x1440 native screen, you still have USB 3.0 access. 3840x2160 is roughly 2.25x the size of 2560x1440 in actuality, so I'm guessing bandwidth is severely starved on older MacBooks and the 2017 is just barely passable.

Interesting. I wasn't aware of that.

And good to see that it can drive a Samsung T5. I have the T5 as well. Note though that the T5 is one of the lower power consumption units, as it maxes out at 3.5 Watts.

Yeah, I think it only works when you have a 4K screen connected, though. 2.5K will still allow you to retain full USB 3.0 bandwidth.

So I couldn't have true 4k on the external monitor and it perform good?

You can. But note that "true 4K" on the Mac is only when you do either native 3840x2160 without scaling, or 1920x1080 scaled in HiDPI mode. Anything else in between will scale the framebuffer up to a much higher resolution. You can take a screenshot and confirm this. So at those much higher resolutions, the 2016 MacBook will suffer. A lot.

Depending on your screen size, 3840x2160 may look super tiny and 1920x1080 may look like... massive (say, especially on a 27 inch display or larger), so you'll always want to scale in between. And if you are doing any scaling, the 2017 MacBook with much better graphics will help a lot.
 
I'm talking about scaling 5120x2880 to a 3840x2160 screen. It's "effectively" scaling 5K to 4K. The 2016 MacBook will slow to a crawl with that. The 2017 is... passable.
I don't understand. What 5K screen are you talking about? The 12" MacBook is not compatible with the LG 5K Ultrafine screen.

Also if you are using a 2560x1440 native screen, you still have USB 3.0 access. 3840x2160 is roughly 2.25x the size of 2560x1440 in actuality, so I'm guessing bandwidth is severely starved on older MacBooks and the 2017 is just barely passable.
Actually, I'm not using any external screen 99% of the time. I just needed a dongle for presentations, and even then it's usually just 1080p60. Rarely is it 2160p60. The 1440p60 was just a test to see if it worked with my 2010 iMac in Target Display mode. It does, but it's usually paired with my 5K iMac for a matching dual 27" setup.
 
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Well, I guess it's hard to describe so here's a screenshot. Note the actual resolution of the screenshot.

UxBR1r4.jpg


The way Mac OS does it is... if you're doing 2560x1440 "equivalent" on a 4K screen, then the OS pushes the internal resolution to 5120x2880 before scaling everything to fit the 3840x2160 resolution of the display. It's not "real" 5K, but the computer is effectively running 5K resolution internally.

This is very taxing on the graphics card. The 2016 model will chug and stutter to no end even with simple things such as opening Launchpad. The 2017 model is just passable in this mode.

But then the problem (at least for me) is that... my display is 27". If I run the panel at "native" 4K, which is either 3840x2160 or 1920x1080 "equivalent", it'll look too tiny or too massive. 2560x1440 is "just right" for a 27" - 30" display, but the MacBook will struggle because it's trying to run a 5K virtual desktop before scaling it down to 4K.
 
Well, I guess it's hard to describe so here's a screenshot. Note the actual resolution of the screenshot.

UxBR1r4.jpg


The way Mac OS does it is... if you're doing 2560x1440 "equivalent" on a 4K screen, then the OS pushes the internal resolution to 5120x2880 before scaling everything to fit the 3840x2160 resolution of the display. It's not "real" 5K, but the computer is effectively running 5K resolution internally.

This is very taxing on the graphics card. The 2016 model will chug and stutter to no end even with simple things such as opening Launchpad. The 2017 model is just passable in this mode.

But then the problem (at least for me) is that... my display is 27". If I run the panel at "native" 4K, which is either 3840x2160 or 1920x1080 "equivalent", it'll look too tiny or too massive. 2560x1440 is "just right" for a 27" - 30" display, but the MacBook will struggle because it's trying to run a 5K virtual desktop before scaling it down to 4K.
Can’t you just get a non-4K dongle and run at 1440p? The monitor itself can do the upscaling to 2160p.

Or is it not possible to just force 1440p using a 4K dongle?

Edit:

Ah I see. I just tried it. Apple won’t let you output at 1440p. I wonder if a third party software utility would allow it.

And yeah, performance really suffers on my 2017 Core m3 MacBook with the simulated 1440p using Apple’s native settings options. Office applications are fine but when I tried the simulated 1440p on my 4K HDR TV and played a high bitrate 4K 10-bit HEVC file on the TV, and also streamed Netflix HD on the laptop screen simultaneously, the Netflix video would occasionally stutter. Performance was fine if I switched the external screen setting to either 2160p or 1080p, as you said.

OTOH, when I tried a native 1440p screen (2010 27” iMac), performance was also fine with my 2017 MacBook driving it.
 
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Yeah, it's weird how Apple is handling resolution right now. A different dongle would only allow 1080p 60Hz or 4K 30Hz on a 4K display. You kinda need to connect to a native 1440p display for that resolution to come up at all.

I do have access to SwitchResX, which does allow forcing any random resolution, including arbitrary scaled HiDPI resolutions between 3840x2160 and 5120x2880 like the immediate 4096x2304 or 4608x2592, both of which are better than the "effective" 1920x1080 UI look, and aren't too taxing on the computer like the 5K setting. The drawback is I had to disable SIP.

But for a user who isn't willing to purchase SwitchResX for long-term use, or has the patience to go through the hoops required to get it working on Mojave, having a 2017 MacBook is still the better bet than 2016 IMHO.

As a side note, I had Windows 10 installed via Bootcamp a while back, and... it had none of this scaling performance issue because the way Microsoft does it is via real UI element scaling, not resolution doubling like Apple.
 
Well, I guess it's hard to describe so here's a screenshot. Note the actual resolution of the screenshot.

UxBR1r4.jpg


The way Mac OS does it is... if you're doing 2560x1440 "equivalent" on a 4K screen, then the OS pushes the internal resolution to 5120x2880 before scaling everything to fit the 3840x2160 resolution of the display. It's not "real" 5K, but the computer is effectively running 5K resolution internally.

This is very taxing on the graphics card. The 2016 model will chug and stutter to no end even with simple things such as opening Launchpad. The 2017 model is just passable in this mode.

But then the problem (at least for me) is that... my display is 27". If I run the panel at "native" 4K, which is either 3840x2160 or 1920x1080 "equivalent", it'll look too tiny or too massive. 2560x1440 is "just right" for a 27" - 30" display, but the MacBook will struggle because it's trying to run a 5K virtual desktop before scaling it down to 4K.

This is such a good explanation to a problem I never thought existed. Wow. And I once thought Apple's scaling implementation is superior to Windows. I guess this is the one drawback to Apple's method.

I guess the only real option in your case would be to run it at 1080 Retina (4k actual) and scale websites down to fit more on the screen.
 
Apple's implementation is somewhat superior to Windows in the sense that all apps should scale without needing specialized UI layouts. So it's good for app developers, but performance suffers.

Also, note that running a real 5K display will skip the "scale to fit" part so I'd say... that's less taxing than running 5K virtual. I'm guessing that's why the iMac 5K is really 5K and not 5K scaled to 4K even though Apple could do it that way, too, to save cost.

Either way, I'm good with using SwitchResX to run the display at the immediate resolution of 4608x2592 (about 2304x1296 effective). I think that's the upper limit of the 12" 2017 MacBook. But seriously, when I had the 2016 MacBook, no matter if it's m5 or m7 model, the computer couldn't take anything past native 4K.
 
BTW, to change the subject a little bit:

With my 5K iMac and my 2.5K iMac in Target Display mode beside it, I'm pleased at just at how well it works. The 2.5K iMac looks obviously worse on close inspection, but for certain usage it's fine, and it saves me from having to buy a 5K external screen for the time being.

What really struck me as an example of great implementation, is that when I move a window from the 5K screen to the 2.5K screen, the window size and the elements within the window all stay the same size. So as I move the window over and have half on a 2.5K iMac and the other half on the 5K iMac, they look like as if they are identical screens, even though one side has 4X the resolution of the other side.
 
Apple's implementation is somewhat superior to Windows in the sense that all apps should scale without needing specialized UI layouts. So it's good for app developers, but performance suffers.

Also, note that running a real 5K display will skip the "scale to fit" part so I'd say... that's less taxing than running 5K virtual. I'm guessing that's why the iMac 5K is really 5K and not 5K scaled to 4K even though Apple could do it that way, too, to save cost.

Either way, I'm good with using SwitchResX to run the display at the immediate resolution of 4608x2592 (about 2304x1296 effective). I think that's the upper limit of the 12" 2017 MacBook. But seriously, when I had the 2016 MacBook, no matter if it's m5 or m7 model, the computer couldn't take anything past native 4K.

My 2016 m7 dragged like no other when connected to my 27” external 4K monitor. Seeing that somewhere along the way a few months back the soldered ssd drive died while plugged into that display, I’ve gotta get a new laptop. My next MacBook will come with a dGPU even if that means hauling around a 15”. I’m just not willing to deal with that screen tearing again.
 
Well, I guess it's hard to describe so here's a screenshot. Note the actual resolution of the screenshot.

UxBR1r4.jpg


The way Mac OS does it is... if you're doing 2560x1440 "equivalent" on a 4K screen, then the OS pushes the internal resolution to 5120x2880 before scaling everything to fit the 3840x2160 resolution of the display. It's not "real" 5K, but the computer is effectively running 5K resolution internally.

This is very taxing on the graphics card. The 2016 model will chug and stutter to no end even with simple things such as opening Launchpad. The 2017 model is just passable in this mode.

But then the problem (at least for me) is that... my display is 27". If I run the panel at "native" 4K, which is either 3840x2160 or 1920x1080 "equivalent", it'll look too tiny or too massive. 2560x1440 is "just right" for a 27" - 30" display, but the MacBook will struggle because it's trying to run a 5K virtual desktop before scaling it down to 4K.

Hi I'm close to buying a 27" 4K monitor, with my 2017 rMBP with dedicated graphics, should I expect to run into performance issues when driving the monitor at looks like 2560?
 
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