LG 5K UltraFine monitor connection issue

I have an LG 5 K UltraFine monitor. There is a connection issue; sometimes it works, but now it doesn't work at all. I have read that this could be a logic board or Thunderbolt port issue. The repair estimate seems larger than the current value. Looking for any last-minute tips since LG and Apple don't offer support.

iPad Pro, iPadOS 18

Posted on Nov 19, 2025 5:31 AM

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Question marked as Top-ranking reply

Posted on Nov 19, 2025 6:45 AM

the vast majority os display issues users encounter turn out to be inadequate cables for the ferocious high speed r=data transmission rates required to keep a high-end display satisfied, without ANY dropped frames, and for most recent MacOS, without any transmission errors.


that LG 5K Thunderbolt-3 display can only use the ThunderBolt-3 cable that shipped in the box, or another Thunderbolt cable limited to 0.5 meters in length.


if you need more cable length, you MUST use a much more expensive (starts at US$125) ACTIVE ThunderBolt cable.


Thunderbolt 5 cables are high quality, but actually do not support higher signaling rates for this use.

3 replies
Question marked as Top-ranking reply

Nov 19, 2025 6:45 AM in response to glocolan

the vast majority os display issues users encounter turn out to be inadequate cables for the ferocious high speed r=data transmission rates required to keep a high-end display satisfied, without ANY dropped frames, and for most recent MacOS, without any transmission errors.


that LG 5K Thunderbolt-3 display can only use the ThunderBolt-3 cable that shipped in the box, or another Thunderbolt cable limited to 0.5 meters in length.


if you need more cable length, you MUST use a much more expensive (starts at US$125) ACTIVE ThunderBolt cable.


Thunderbolt 5 cables are high quality, but actually do not support higher signaling rates for this use.

LG 5K UltraFine monitor connection issue

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