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Is the LG UltraFine 4K Display compatible with the Early 2015 MacBook Pro 13"?
- Thread starter Falcon9
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The LG UltraFine 4K 21.5 inch display uses USB-C with DisplayPort alt mode - it does not support Thunderbolt (which is a different alt mode).
The Apple Thunderbolt 3 to Thunderbolt 2 adapter does not support USB-C with DisplayPort alt mode.
You can use the Apple Thunderbolt 3 to Thunderbolt 2 adapter to connect a Thunderbolt 3 dock or device, then connect the LG display to the second Thunderbolt port of the Thunderbolt 3 dock or device. The Thunderbolt port of the Thunderbolt 3 dock or device supports USB-C with DisplayPort alt mode.
Or you can try one of the following : Huawei VR 2 Computer Connection Cable, Wacom Link Plus, Sunix UPD2018, Delock 89582.
Thanks Joevt for the quick reply. I do have the Apple adapter and cable with me. I am not sure about what needs to be purchased at this point to connect my early MacBook air 2015 with LG Ultrafine 21.5 4K monitor. Could you please provide the link of the Thunderbolt 3 dock/device you are suggesting. I appreciate your help on this.
Charging Essentials - Mac Accessories
Find cables, charging docks and battery cases for Mac. Charge and sync up your Mac. Buy online with fast, free shipping
www.apple.com
Any Thunderbolt device with two Thunderbolt ports will work. Choose a device with the lowest price, or choose one that might be useful now or in the future.
PCIe expansion boxes allow you to use a PCIe card with your MacBook Pro (you don't need a PCIe card for this purpose but it's an option that might be useful in the future; you could use them to add a GPU - but non-eGPU boxes require additional power supply for power hungry GPU PCIe cards):
Sonnet Echo Express SEL (Thunderbolt 3 edition)
Sonnet Echo Express SE I (Thunderbolt 3 edition)
Sonnet Echo Express SE III-D (Thunderbolt 3 edition)
Google "best thunderbolt 3 docks"
Our Favorite Thunderbolt Dock Is an Upgrade Over a USB Hub
If your computer has Thunderbolt ports, a Thunderbolt dock is faster and more versatile than a USB hub. We have options for every budget.
thewirecutter.com
Some of these may have USB-C power delivery which can charge your laptop (if you buy a new laptop that uses USB-C charger).
Any Thunderbolt device with two Thunderbolt ports will work. Choose a device with the lowest price, or choose one that might be useful now or in the future.
PCIe expansion boxes allow you to use a PCIe card with your MacBook Pro (you don't need a PCIe card for this purpose but it's an option that might be useful in the future; you could use them to add a GPU - but non-eGPU boxes require additional power supply for power hungry GPU PCIe cards):
Sonnet Echo Express SEL (Thunderbolt 3 edition)Sonnet Echo Express SE I (Thunderbolt 3 edition)Sonnet Echo Express SE III-D (Thunderbolt 3 edition)
Google "best thunderbolt 3 docks"
Our Favorite Thunderbolt Dock Is an Upgrade Over a USB Hub
If your computer has Thunderbolt ports, a Thunderbolt dock is faster and more versatile than a USB hub. We have options for every budget.
Some of these may have USB-C power delivery which can charge your laptop (if you buy a new laptop that uses USB-C charger).
I have purchased a new CalDigit dock and tried to connect my MacBook Air 13, 2015 using Apple's Thunderbolt 3 to Thunderbolt 2 adapter and Thunderbolt cable to the dock's thunderbolt's port and connected LG Ultrafine display using the other thunderbolt port but the display is still not working. Am I doing it anything wrong? Please advise.
CalDigit TS3 Plus Dock
The CalDigit TS3 Plus dock uses one of your Mac’s Thunderbolt 3 ports to instantly add up to 15 expansion ports and to provide charging for your MacBook. Buy online now at apple.com.
www.apple.com
Apple Thunderbolt Cable (0.5 m) - White
Apple Thunderbolt Cable lets you conduct fast data transfers by connecting Thunderbolt-enabled devices to your Mac. Get fast, free shipping.
www.apple.com
Does the CalDigit appear in the Thunderbolt devices list? Post a screenshot of the Thunderbolt section of System Information.app. It should show a 20 Gbps link to the CalDigit TS3 Plus Dock.
Can you connect a mouse or keyboard to the dock to make sure it works?
The dock has two Thunderbolt 3 ports. Make sure the Apple Thunderbolt 3 to Thunderbolt 2 adapter is connected to the one marked as "Computer". Connect the LG UltraFine 4K display to the other Thunderbolt 3 port. You may need to power on/off the display or connect it after the computer has started.
With the display connected, get the output from the AGDCDiagnose command and post it here. Maybe we can see a connection problem.
Thank you so much, I was able to connect my laptop with the monitor via doc. Could you please tell me how to connect the iPad that is having a lightning port to the LG Display?
You said it didn't work before. What did you change to make it work?
The LG Display has 3 USB-C ports.
The iPad comes with a USB-A to Lightning cable for charging.
You need a USB-C to USB-A adapter to connect the iPad to the LG.
Or you can connect the iPad to the CalDigit since it has USB-A ports.
Or you can use a USB-C to lightning cable.
Not sure that's quite right... I wouldn't think anyone needed advice about how to actually plug an iPad in for power and data transfer. I'd think OP wanted to achieve video out to the LG display.
I don't think there are any DisplayPort output options for iPads that use Lightning instead of USB-C.
Use a Lightning Digital AV Adapter to get HDMI (up to 1080p)
Then use a Wacom Link Plus to convert HDMI to USB-C.
Thank you for your advice. I have exactly the same problem.
Is there any chance that any of the following will work:
1) USB-C (male) to DisplayPort (full size, female) adapter + Thunderbolt 2 to DisplayPort cable (male)
like this
and
2) USB-C (male) to MiniDisplayPort (female) adapter + Thunderbolt 2 to Thunderbolt 2 (male) regular cable
and
My setup is MacBook Pro 15 Late 2013 & LG UltraFine 4K 21.5" (not 24)
USB-C (male) to DisplayPort (full size, female) adapters usually only work in one direction - from USB-C source to DisplayPort display.
For Thunderbolt 2 to DisplayPort cable, I think you mean Mini DisplayPort to DisplayPort cable. No Thunderbolt signal is involved with those.
The second link is a Mini DisplayPort to HDMI cable. You just posted an image instead of description, so I don't know for sure, but it is most likely Mini DisplayPort computer to HDMI display direction only.
USB-C to Mini DisplayPort adapter is also single direction only - from USB-C computer to Mini DisplayPort display.
In this case the Thunderbolt 2 cable should be a Mini DisplayPort to Mini DisplayPort cable because Thunderbolt 2 cables cannot be used for DisplayPort.
With those two items, there is no Thunderbolt signal.
You need one of the solutions described in #27
Is the mentioned Huawei VR Computer Connection Cable bi-directional?
Huawei VR Computer Connection Cable
Buy Huawei VR Computer Connection Cable » cect-shop.com. ✓ Cheapest Price ✓ Best Quality ✓ Fast Shipping ✓ Best Service ✓ Original Huawei.
www.cect-shop.com
I picked up another configuration without a hub, should I try?
VisionTek USB-C to DisplayPort Bi-Directional 2M Cable +Bi-Directional 3 feet Mini DisplayPort to Display Port Extender Extension Cable
+
SPPRANDOM HOMIEBUDS Bi-Directional 3 feet Mini DisplayPort to Display Port Extender Extension Cable Adapter, DP to Mini DP (Thunderbolt 2 Compatible) Cable Female to Male
Mini DisplayPort to DP extension extender Cable 4K 3 feet Male to Female
www.amazon.com
or
Moshi USB C to DisplayPort Cable 1.5m/5ft, Support 5K@60 Hz, 4K HDR, VESA Certified, Aluminum Housing, Thunderbolt 3 Compatible (Ensure Monitors Accept DisplayPort Signal)
Supports up to 5K video resolution with 4:4:4 chroma subsampling, supports High Dynamic Range & Bi-directional support
www.amazon.com
3.3 ft. (1 m) USB-C to DisplayPort 1.4 Cable - Bi-Directional
Unparalleled Performance Supporting four times the resolution of 4K, this 8K DP 1.4 adapter cable delivers the stunning quality of UHD at resolutions up to 7680×4320, and also features HBR3 functionality, providing a bandwidth of up to 32.4Gbps. The video cable is backward compatible with 4K and ...
www.amazon.com
all of those listed as bidirectional, which one is better? (I will keep the scheme with the dock as the last resort)
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
No. It's DisplayPort 1.2 and USB-A from computer to USB-C display.Is the mentioned Huawei VR Computer Connection Cable bi-directional?
Huawei VR Computer Connection Cable
Buy Huawei VR Computer Connection Cable » cect-shop.com. ✓ Cheapest Price ✓ Best Quality ✓ Fast Shipping ✓ Best Service ✓ Original Huawei.
You want to combine the second link with the Huawei VR Computer Connection Cable to make it work from Mini DisplayPort + USB-A to USB-C display.
Of the three USB-C to DisplayPort bidirectional cables, only the Moshi is VESA certified but it's more expensive. Amazon has a good return policy so you can try the cheaper ones.
USB-C Adapters Archives - DisplayPort
Some displays like the old LG UltraFine 4K require a USB signal with the DisplayPort signal, so you need a method to combine both #27
Read this thread https://hardforum.com/threads/use-usb-c-monitor-without-usb-c.1911817/