Recent LTT video on LG Ultrafine Monitors

[Umang Goel]

In the recent video by LTT, Linus said that Thunderbolt 3 on Windows can't run 5K, but wasn't TB3 always advertised as capable of running 2 4K displays @ 60Hz each, then why can't it run 5K? 

 

And can't even the PCIe 3.0 x4 TB3 expansion cards run 5K@60Hz  ?

[EunSoo]

I haven't watched the video and I will probably have some similar issues with it. But the concept of it can be explained. Think of the standard as a toaster. 4k can be like a regular piece of white bread that can easily fit into the toaster, no problem. 5k would be like a piece of sourdough which (depending on the loaf and toaster) will usually not fit in the toaster. The toaster has two slots that can easily fit 2 pieces of white bread (4k monitors) and if those two slots were put together then they could fit a sourdough slice (5k monitor) but those two slots just can't be arranged like that. That concept is the same that can be applied to technology and of course, that is a very distorted way to explain it but hey, it works. 

[Glenwing]

3 hours ago, Umang Goel said:

In the recent video by LTT, Linus said that Thunderbolt 3 on Windows can't run 5K, but wasn't TB3 always advertised as capable of running 2 4K displays @ 60Hz each, then why can't it run 5K? 

 

And can't even the PCIe 3.0 x4 TB3 expansion cards run 5K@60Hz  ?

Depends on implementation, single-port TB3 controllers are limited to 4 lanes of DisplayPort 1.2 (max 4K 60 Hz), while dual-port TB3 controllers have up to 8 lanes of DP 1.2, which can be allocated to a single port if desired (so max 4K 120 Hz or 5K 60 Hz or 2× 4K 60 Hz, though using the full bandwidth on one port will disable video capability on the second port). I haven't looked into it but I gather that's not how most aftermarket motherboards with TB3 are set up.