# Does all 4k TVs support chroma 4.4.4 when using hdmi 2.0 cable ?



## r9 (Mar 29, 2020)

I'm exploring the option to get 43" 4k tv and use it as a monitor.
I've been looking into it a bit and I was testing on my 50" 4k tv.
I found out that you need hdmi 2.0 cable to be able to do 4k@60+Hz and chroma at 4:4:4.
Currently I have it connected with 1.3 hdmi and I can either do 4k@30Hz with 4:4:4 or 4k@60 4:2:0, which is fine for games but not so much for text as a monitor.
For those who wonder here's the difference:


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## xBruce88x (Apr 6, 2020)

It's not so much the cable but that both devices need to fully support hdmi 2.0. As far as I know, the cable is physically the same regardless. 

As far as the original question, it depends on what hdmi spec the TV follows


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## Mussels (Apr 6, 2020)

Most 4K HDR TV's support it, but some only support it on one HDMI port as well - my first samsung only supported one port while my sony supports all, but you have to enable it in the TV's settings for each port.


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## sneekypeet (Apr 6, 2020)

I have to run the tv in HDR mode, for the picture,  at least I think that's it. Then go into the gpu software and use the custom options to use 4:4:4. That's 4k 60hz.


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## TheLostSwede (Apr 6, 2020)

xBruce88x said:


> It's not so much the cable but that both devices need to fully support hdmi 2.0. As far as I know, the cable is physically the same regardless.
> 
> As far as the original question, it depends on what hdmi spec the TV follows


Not quite true, as HDMI 1.3 and older cables are not the same quality as HDMI 1.4 and 2.0 cables.
HDMI cable 1.0 – 1.2 – no 4K Ultra HD support​HDMI cable 1.3: Probably no 4K support depending on the cable​HDMI cable 1.4: 4K support very likely, but not guaranteed​HDMI High Speed Cable: 4K Ultra HD support guaranteed​Source: https://turbofuture.com/computers/do-i-need-hdmi-cable-4k-hdmi-20-guide
Also: https://www.hdmi.org/resource/cables

As the OP has an HDMI cable, it seems it wasn't designed to handle the extra bandwidth, so his devices drop back to 4:2:0 to be able to maintain the 4K signal. What is needed is a High Speed cable.
HDMI 2.1 again will require Ultra High Speed cables, which can handle 48Gbps of bandwidth.


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## skizzo (Apr 6, 2020)

it can vary TV to TV. best bet is to read up a review on a detailed site like www.rtings.com for the model you want to know more about

Even some TV's with HDMI 2.0 can only show proper 4:4:4 at for example certain resolutions and/or refresh rates. For example, Samsung's NU8000 can do 4:4:4 at 4K 60Hz but it can NOT do 4:4:4 at 1440p at 120Hz or even just 60Hz. Lots of TV's make you label the HDMI input as "PC" or "Computer" or something similar in order for the TV to go into whatever "mode" that manufacture calls it to allow the TV to use low input lag and proper display of 4:4:4 etc

Generally speaking though, if it has HDMI 2.0 yes it should be able to do 4K 60Hz 4:4:4 but it is best to know the details for the TV set you are interested in purchasing. Like others mentioned you need a GPU which can output the proper signal too, so a GPU with at least HDMI 2.0, preferably 2.0b


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## Fluffmeister (Apr 6, 2020)

Yeah a high quality cable is really important too, the original cable I bought was supposed to be a good quality hdmi2.0 4K cable and would do 4K 4:2:0 @ 60Hz all day long. But my TV required that I enabled enhanced mode on the hdmi ports to enable 4:4:4, doing that with that cable would just result in a blank screen.

Bought a hdmi 2.1 cable and voila! Enhanced mode worked and I was away:


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## X71200 (Apr 6, 2020)

Not all TVs can do 4:4 regardless of cable. Lower end 4k TVs from older years, were for a long time, simply incapable of doing 4:4 on PC. For example, with LG, the 650V models couldn't while the 850 could.


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## R-T-B (Apr 6, 2020)

chroma 444 support on TVs has always been a crapshoot.  Don't bet on it, research.


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## Fluffmeister (Apr 6, 2020)

X71200 said:


> Not all TVs can do 4:4 regardless of cable. Lower end 4k TVs from older years, were for a long time, simply incapable of doing 4:4 on PC. For example, with LG, the 650V models couldn't while the 850 could.



Of course, but the point was not all cables are made equal.


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## Mussels (Apr 7, 2020)

I have to agree on cables, i've got antique short ones that work fine, but as the length grows cable quality needs increase


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## R-T-B (Apr 7, 2020)

Cable length is a strange thing.

On the HDMI side of things, it's actually well defined:  The cable must meet it's rated speed at the length it is sold at to be considered "certified."  Note however, not all HDMI cables bother getting certified, and a lot of the cheap ones claim to be but aren't.

On the displayport side, the cert is looser:  The cable only needs to meet it's speed rating at up to 2 meters, and up to full length at a reduced speed mode meant for projectors that really can't do more than 1080p.  This means in practice, a lot more cables bother getting certified, but almost anything over 2 meters is a crapshoot if not buying high end.  Really, just buy a cert'd 2 meter cable and get a good repeater to go in the middle if you need a long cable.

So yeah, cable quality does matter, but at least in some cases, a cert from the org in question can help you know certain things, too.  But really, a repeater is a good answer to the length equation, often better than a super long expensive cable.


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