While at a trade show, I had the opportunity to try out the new LG UltraFine 5k
and Ultrafine 4K
The good news is that these are VERY impressive displays visually. While not OLED, the blacks are deep as if you're looking back into the depths of space. The wider color gamut was noticeable and it was being sent a true 30 bit image. Now the slew of downsides. It appears that this is a Mac exclusive for the time being. I brought over my Dell m5510 with a Thunderbolt 3 port and no picture was displayed, just a blank white image. My system did recognize a new Thunderbolt 3 device and I saw an additional display in both Window's display settings and the nVidia control panel. After testing this unit out and double checking driver versions, I did notice that I'm one version behind the most recent Quadro and Intel GPU driver releases. November was a busy month for me (hooray ~70 hour work weeks and no weekends!). The other downside is that it was running at a 2560 x 1440 resolution at 30 bit color according to System Profiler. Not sure if this is just how Apple under reports retina resolutions as the text did appear to be rendering at a higher resolution (or that Apple's text anti-aliasing is really good with 30 bit output).
The Ultrasharp 4K really does live up to its name. 4096 x 2304 pixels in a 21.5" form factor means incredibly small pixels. The exceptional blacks and overall larger color gamut from the 5K unit are also found on the 4K machine. Unlike the 5K unit, this one does not inherently use Thunderbolt 3. Rather this simply uses the DisplayPort USB Type-C alternative mode so I was hoping for some greater compatibility. Unfortunately I didn't have a vanilla USB Type-C to C cable handy so I simply reused the Thunderbolt 3 cable from the 5K unit since it was readily available. How my system behaved with this was genuinely weird. It got caught in a loop producing dialog boxes and having my screen flicker as if it reconnected to the monitor. With this software glitch, I was not able to see how it interfaced with a Windows laptop. I'm a bit more optimistic that this display would have worked if I had used a non-Thunderbolt 3 cable. Oddly, those Thunderbolt 3 cables are supposed to function as active USB Type-C cable when connected between two non-Thunderbolt 3 devices.
A general note about the Macbook Pro 13" driving the 5K display is that the end of the Thunderbolt 3 cable got noticeably hot. Both the 4K and 5K displays were designed to provide 85W of power and you certainly can feel it in the cable. Well not all 85W but you know that it is powering/charging the Macbook Pro.
Anyway, I should give a shout out to LG to at least letting me try this. I do agree with their assessment that after a few driver updates on the PC side this should work without issue. Considering that the 5K unit isn't even arriving to the door steps of early adopters until next week, there is time to get the updates out.