4K or UltraHD Displays and Your PC

What Are They and What It Will Require of Your PC or Tablet

ASUS PA328Q 32-inch 4K UIltraHD PC Display
ASUS PA328Q 4K Display. ©ASUSTeK

Traditionally, computer displays have had an advantage over other home electronics when it came to a resolution. This began to change once high definition television was introduced to consumers and finally adopted by the government and broadcasters. Now HDTVs and most desktop monitors share the same resolution but mobile computers for the most part still come equipped with displays of lower detail.

This has changed somewhat after Apple began releasing their Retina based displays but now with the finalized 4K or UltraHD standards, consumers can now get displays that offer some incredible detail than in the past. There are certain implications if you are thinking of getting and using a 4K display with your computer.

What is 4K or UltraHD?

4K or UltraHD as it is officially called is used to reference a new class of super high definition televisions and video. The 4K is in reference to horizontal resolution of the image of the picture. Typically, it is either 3840x2160 or 4096x2160 resolutions. This is roughly four times the resolution of the current HD standards that top out at 1920x1080. Even though these displays can go extremely high, consumers have little avenue for actually getting 4K video to their displays as there is no official broadcast standard for it in the US yet and the first 4K Blu-ray players have only recently made it to market.

With 3D video not really taking off in the home theater market around the world, manufacturers are now looking at UltraHD as a means to push the next generation of home electronics on consumers. There are a large number of 4K or UltraHD televisions available on the market and PC displays are also becoming more common for desktops and even integrated into some high-end laptops.

Using these displays does have certain requirements, though.

Video Connectors

One of the first problems that computers will have trying to run 4K or UHD monitors is going to be the video connectors. The very high resolutions require a large amount of bandwidth in order to transmit the data required for the video signal. Previous technologies such as VGA and DVI simply can't handle those resolutions reliably. This leaves the two most recent video connectors, HDMI and DisplayPort. It should be noted that Thunderbolt will also support these resolutions as it is based on the DisplayPort technology and connectors for video signals.

HDMI is used by all consumer electronics and is likely going to be the most common type of interface you will see on the earliest of the 4K HDTV monitors on the market. In order for the computer to use this, the video card will need to have an HDMI v1.4 compatible interface. In addition to this, you will also need HDMI High Speed rated cables. Failure to have the right cables means that the image will not be able to be transmitted to the screen at the full resolution and will fall back to the lower resolutions. There is another less publicized aspect of HDMI v1.4 and 4K video as well.

It is only able to transmit a signal with a 30Hz refresh rate or 30 frames per second. This may be acceptable to watching movies but many computer users, specifically gamers, want to have at least 60fps. The newer HDMI 2.0 specification corrects this but it is still uncommon in many PC display cards.

DisplayPort is the other option that will likely be used by many computer displays and video cards. With the DisplayPort v1.2 specification, a video signal over compatible hardware can run the full 4K UHD video signal up to 4096x2160 with the deep color and 60Hz or frames per seconds. This is perfect for computer users that want a faster refresh rate to reduce eye strain and increase fluidity of motion.

The downside here is that there is still a lot of video card hardware out there that does not have DisplayPort version 1.2 compatible ports. This may mean that you will need to upgrade to a newer graphics card if you want to use one of the new displays.

Video Card Performance

With most computers currently using 1920x1080 high-definition display resolutions or lower, there hasn't been much need for high-performance graphics cards. Every graphics processor whether it is integrated or dedicated can handle basic video work at the new 4K UHD resolutions. The issue is going to come with the acceleration of video for 3D users. At four times the resolution of standard high definition, that means four times the amount of data needs to be processed by the graphics card. Most existing video cards will not have the ability to reach those resolutions without significant performance problems.

PC Perspective put together a great article that looked at the performance of existing video card hardware attempting to run some games on an early 4K television over HDMI. They found that if you want to even attempt to run games at a smooth 30 frames per second, you pretty much are required to purchase a graphics card that costs in excess of $500. This isn't extremely surprising as these are the cards that are pretty much required if you planned on running multiple monitors to get a higher resolution display. The most common multiple display setup for gamers is three 1920x1080 displays to generate a 5760x1080 image. Even running a game at that resolution only produces three fourths of the data required to run at the 3840x2160 resolution.

What this means is that while the 4K monitors are getting more affordable, the graphics cards still lag behind the video hardware for some time when it comes to gaming. It will probably take three to four graphics card generations before we see truly affordable options that can handle gaming at the high resolutions. Of course, it will probably take just as long to see the monitor prices drop as it took many years before 1920x1080 displays became extremely affordable.

New Video CODECs Needed

A greater percentage of the video that we consume is coming from sources over the internet rather than traditional broadcast means. With the increase in the data stream size of four times from the adoption of Ultra HD video, huge burden will be put upon internet traffic not to mention the file sizes for those that purchase and download digital video files. Suddenly your 64GB tablet can only hold one quarter as many movies as it once did. Because of this, there is a need to create more compact video files that could be transmitted more efficiently over the networks and keep file sizes down.

Most of the high definition video now uses the H.264 video CODEC from the Moving Picture Experts Group or MPEG. Most people probably just refer to these as MPEG4 video files. Now, this was a very efficient means of encoding data but suddenly with 4K UHD video, a Blu-ray disc could only have one-quarter of the video length on it and streaming video takes up four times the bandwidth which saturates network links especially at the user end very quickly. To solve this issue, the MPEG group began working on H.265 or High Efficiency Video CODEC (HEVC) as a means to reduce the data sizes. The goal was to reduce file sizes by fifty percent while keeping the same level of quality.

The big downside here is that much of the video hardware is hard coded to use the H.264 video in order to be as efficient as possible. A good example of this is Intel's HD Graphics solutions along with Quick Sync Video. While this is hard coded to be extremely efficient with HD video, it is not going to be compatible at the hardware level for dealing with the new H.265 video. The same is true for many graphics solutions found in mobile products. Some of this can be handled through software but it means that many existing mobile products such as smart phones and tablets may not be able to playback the new video format. Eventually this will be solved with new hardware and software.


4K or UltraHD monitors and displays are going to open up a new level of realism and detailed imagery for computers. This is, of course, going to be something that most consumers won't see for many years because of the high costs involved in producing the display panels. It will take many years for the displays and the video driver hardware to be really affordable for consumers but it is nice to finally see some interest in higher resolution displays after the average resolution of most mobile laptops being sold still be stuck resolutions below 1080p high definition video.