How to use a 4K TV as a computer monitor

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  1. Have a video card with at least hdmi 2.0, or use a displayport into hdmi 2.0 adapter to get fidelity. (yuv 444)
  2. Find a tv that does said yuv 444 at full framerate. (60hz)

(for most video yuv 422 isn’t a big deal, but when you display computery things like text the reduction in quality is noticeable.)


Isn’t a 24" monitor more like 1/4 of a 50" monitor? They measure them on the diagonal, so try to visualize it.

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Headline stinks. I came here to learn how to use a 4k tv as a monitor. From the title I assumed the suggestion is more than just hooking hdmi in to hdmi out. Yet… I’m greeted by it’s neat and can be amazing if you tweak it. :expressionless:


IKR? My 4k telly refuses to show up as 4k; it just seems to report itself as a generic 1080p display. The only way I could get 4k out of it was to test a custom resolution mode that for some reason wouldn’t work beyond the test; I couldn’t make it stick.

Then my only 4k input decided to apparently stop working, dammit. Glad I only paid $400…

Plug it in. Have a video source that supports 4k.

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So, I’m sitting in front of a retina 5k imac, and for acouple of months, I’m hearing a great deal of information on how my machine-- a 4690k-- is going to be so very obsolete because it can’t decode h.265, and DRM and what not…

( I have much worse things to worry about, anyway. Seems a certain Fire is on Mom’s doorstep :worried: )

Where are you reading that? It should be handled by the OS, and you should be fine:

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I’m pretty sure I could get one if I wanted to. For free, too.


My 2011 iMac plays h.265 video files just fine.

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Yes, the area is about a quarter. The diagonal is irrelevant, though- if you double the diagonal, the length and height will also double (assuming both screens have the same aspect ratio).

I’m guessing that his point is that the pixel size is roughly the same on a 24" HD (1920x1080) as it is on a 50" 4K (3840x1920). This means that text and images appear at the same physical size, so you’d want to sit at the same distance for both.

Huh. I was literally (in the next half hour) about to buy a 4K 27" monitor and now I don’t know what to do :frowning:

Not sure if this helps (it won’t) but occasionally I’ll drag the computer from the office down into the TV room (to give me space for VR). And I notice I get what I hope is temporary screen burn on the TV pretty quickly, after-images of windows and toolbars that take a long while to fade away.

While of course there isn’t that issue with monitors. Which I assume is why monitors cost a lot more than TVs.

I’m not sure if I’d want to use the TV as a PC screen long-term.

Well, “assuming both screens have the same aspect ratio”, the diagonal is totally relevant. We agree though, that in that scenario (same aspect ratio) the area is actually about 1/4.

Given they will have roughly the same pixel size, it is pretty tempting to use a 4K TV as a monitor, but may not be a very good idea. Despite the equal pixel size, text will probably not look very good on the TV. This has to do with chroma 4:4:4 vs chroma 4:2:0 (which is probably what you would find on the TV). Also, input lag will probably be considerably greater on the TV. You probably wouldn’t notice it if you’re watching video, but a TV would suck for gaming.

My setup is a 24" monitor for the primary display and an HD projector for relaxing with video. Projectors are also getting cheaper.

Interesting. I think I’d assumed that screen burn (temporary or otherwise) was a thing of the past. Out of interest, how old is your TV?

For my old setup when my PC was in the living room, I had my TV hooked up as a second screen for watching videos and gaming, and it looked great. That was regular HD rather than 4K but I wouldn’t have thought it’d be any different.

Also, what about games consoles? There’s no problem using them.

About a year, so pretty new and pretty large, 50" thereabouts.

That’s the weird thing, I can play a console game for hours that has a persistent UI element (mini-map, health bar) and it doesn’t seem to have any after-image. But doing the same with the PC and things burn in pretty quickly. For example I have Diablo 3 on both PC and console. Those health/mana orbs on the UI persist for a good while after playing the PC on the TV, but hardly anything with the console, there’s a bit, but it takes longer and goes away quicker.

I have no explanation for why this should be, it just how it is, and totally anecdotal of course. But yeah, I try not to use my PC with the TV too much. You’ll most likely be fine.

I got a 4k Visio a few months ago to do just this. I have a Mac mini 2012, with just barely not enough video output to run it…so I got a Diamond USB 3.0 video display adapter and a free app that I don’t recall the name of right now (I’m away from my home computer as I write this.)

Now I can use the TV at 4k when I want to - which is generally when editing photographs in Lightroom. I can really see the whole picture pretty clearly.

Video is still choppy at 4k. A new mac might rectify this, but I’m good with how it is right now.

Very strange. Maybe something to do with the signal or refresh rate or something?

what resolution, and what player?

1080p, VLC. Computer is the fully loaded 27" with 8 core i7. Playback of x.265 does not seem to churn the CPU or GPU.

Worth noting that the space savings with 265 are so great that I’ve been re-ripping all my blurays. Doctor Strange came down to 1.6GB using Handbrake.

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