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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.

30 bit color?  I thought 10 bit was the highest...

DPete27 wrote:

30 bit color?  I thought 10 bit was the highest...

They probably mean 30 total (so 10 per color).

Correct. 10 bits per channel for 30 bit total.

But what about the refresh rate? 4k is hindered by 60Hz (IF you have the hardware to attain that). So whats 5k, like 32Hz??? Sure they look good but for PC practicality and the master race not-so-much.

tanker27 wrote:

So whats 5k, like 32Hz??? Sure they look good but for PC practicality and the master race not-so-much.

Am I the only one old enough to remember the days when a solid 30 FPS with all the goodies on was the "gold standard"?

tanker27 wrote:

But what about the refresh rate? 4k is hindered by 60Hz (IF you have the hardware to attain that). So whats 5k, like 32Hz??? Sure they look good but for PC practicality and the master race not-so-much.

For the Apple products using that panel (first time on an Imac a few years back?), they overclocked the controller to keep it at 60Hz.

But it is certainly nice to see that LCD's are still getting iterated in a positive direction, given that OLEDs aren't quite ready for prime-time yet.

Captain Ned wrote:

Am I the only one old enough to remember the days when a solid 30 FPS with all the goodies on was the "gold standard"?

No, I remember this too.

Airmantharp wrote:

But it is certainly nice to see that LCD's are still getting iterated in a positive direction, given that OLEDs aren't quite ready for prime-time yet.

I guess your definition of "iterated in a positive direction" differs from mine. I don't feel this is a positive direction. Sure squeezing more pixels in is good, but the refresh rate is abysmally slow IMHO.

Airmantharp wrote:

But it is certainly nice to see that LCD's are still getting iterated in a positive direction, given that OLEDs aren't quite ready for prime-time yet.

tanker27 wrote:

I guess your definition of "iterated in a positive direction" differs from mine. I don't feel this is a positive direction. Sure squeezing more pixels in is good, but the refresh rate is abysmally slow IMHO.

It's the same as increasing framerate on lower resolution monitors; both are limited by overall DP bandwidth. But better overall IQ, including accurate broad-spectrum color and deep blacks? Great! Higher variable refresh rate versions will come in due time.

Both the 4K and 5K unit were being driven at 60 Hz refresh rate from a Mac. DP1.2 has enough bandwidth to do cinema 4k, though barely.

DP1.3, which isn't actually used here, can 5K over a single cable. A bit of Thunderbolt 3 hackery is done to encapsulate two independent DP 1.2 stream over a single cable. Each stream drives half of the 5K display even though logically it is seen as one single unit. Even my Dell laptop saw it as a single display even though it didn't display nothing except a pure white image.

Previous 5K displays used two DP cables to drive 5K content due to DP 1.2 bandwidth limitations.

Edit: clarified DP 1.2 resolution for 4k

the wrote:

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).

There is something odd about that. I just checked one of our 5K iMacs and it reports as "5120 x 2880 Retina" in the System Information app.

"Deep Space Blacks"? That's pretty cool, I'll have to check out this display.

Maybe IQ has improved enough to be where Plasma TVs were 10 years ago! We live in exciting times!

DPete27 wrote:

30 bit color?  I thought 10 bit was the highest...

No, there's 12, 14, 16 and with the right LUT you should be able to output 64 and 128 bits per color channel.

End User wrote:

the wrote:

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).

There is something odd about that. I just checked one of our 5K iMacs and it reports as "5120 x 2880 Retina" in the System Information app.

Yeah, that resolution seemed as if it was out of place. Not sure if Sierra changed how resolutions are reported as often a retina display will behave in terms of layout as if it were a lower resolution display. Unfortunately I wasn't able to swing by again after updating my drivers to give it a shot.

Vhalidictes wrote:

"Deep Space Blacks"? That's pretty cool, I'll have to check out this display.

Maybe IQ has improved enough to be where Plasma TVs were 10 years ago! We live in exciting times!

The screen had to have been calibrated rather well. This conference had Barco showing off their diagonistic displays. You really don't find a better display than those and the LG units were holding there own rather well in terms of black level. Only way to further improve them is with OLED or Panasonic's new technology.. On that note, I'm kinda surprised that I didn't see Panasonic at that trade show demoing that unit as on paper it would have been competitive.

Vhalidictes wrote:

Maybe IQ has improved enough to be where Plasma TVs were 10 years ago! We live in exciting times!

I'll give you my Samsung PNF8500 when you pry it from my cold, dead hands!