4K vs 8K HDMI Cables: A Quick Guide
4K vs 8K Basics
Both types of cables are HDMI, and they are used for ultra-high-definition video. 4K is known as HDMI 2.0, and the cables support video at resolutions up to 2150p (3840 X 2160), which comes out to roughly 8 million pixels in an image.
8K is known as HDMI 2.1, and the cables double those numbers to provide 4320p (7680 X 2160) which gets the pixel count all the way up to 33 million.
Those basic distinctions form the basis of all comparisons between the two types of cables, but if we want to take a deeper look, we’ll need to cover some similarities and additional differences between the cable types.
Key Similarities Between 4K and 8K
These are both HDMI cables. That means they use the same form factor, and they are both reverse compatible with older forms of HDMI.
That said, it’s important to understand how reverse compatibility works. An 8K or 4K cable can absolutely connect a legacy DVD player to an older TV. The catch is that you won’t get the maximum resolution capable from your cable unless all of the attached hardware can keep up. So, if you use an 8K cable to connect older devices that cap out at 1080p, then the video you see will only be 1080p.
As for differences, we’ve already covered the resolution differences, but there are a few other specifications worth considering.
4 cables provide data bandwidth up to 18 Gbps. With this, they support 4K videos at a maximum refresh rate of 60 Hz. For reference, 60 Hz is the standard refresh rate for movies in a theater. Lastly, 4K cables provide up to 32 audio channels and sample sounds at 1532 kHz.
As for 8K cables, they achieve bandwidth up to 48 Gbps and can provide a resolution of 10K at 120 Hz. 8K cables also provide eARD, Dynamic HD, and DSC, all of which offer improved video quality.
Which Should You Use?
As far as specifications go, 8K cables are superior in every way, so you should stick with them, right?
Not so fast.
First off, 8K cables cost more than 4K cables. That might be worth it if you could reliably get 8K quality out of all of your hardware and data streams, but that won’t be the case. 8K is still relatively new in the tech world, and there are plenty of circumstances where it is completely unavailable.
Let’s look at a few common use cases to see when 8K shines and when it might cost more than it is worth.
Hooking up a DVD player (not a BlueRay player) isn’t the most common practice in the world these days, but this allows us to highlight why hardware performance matters when you choose your HDMI cables.
For a traditional DVD player, you can’t get resolution up to 4K (much less 8K). The best cable to use in this scenario is traditional HDMI.
Still, there are plenty of modern setups that do reach 4K and/or 8K resolutions. Your most common ultra-high definition stuff will currently operate at a 4K resolution. If your video caps at 4K, then use 4K cables. It really is that easy.
If you’re not sure about your maximum resolution, 4K is a safe bet. While 8K does exist, broadcasts at this resolution are rare. Most gaming consoles and streaming services still cap at 4K, although there are some exceptions (in the next section).
The only time you actually need to use 8K cables is when you have access to 8K content. Where do you find 8K content?
YouTube is arguably the most abundant resource. Not all YouTube videos and streams are available in 8K, but you’ll find more 8K video here than anywhere else.
You might find limited 8K access with other leading streaming platforms, but most 8K streaming is still in an experimental phase, and access is extremely limited.
Much of your 8K content will actually be video you make yourself. Plenty of high-end phones and dedicated cameras can produce 8K video and images. If you want to enjoy them, then 8K cables are part of the equation.
High-End PC Gaming
Lastly, we come to high-end PC gaming. 8K cables are not absolutely necessary for PC gaming, but if you are trying to push your refresh rate as high as possible in a game, 8K cables are worth the investment.
That about does it. Those are the primary times when you need 8K and 4K HDMI cables. In other circumstances, you can get away with saving money and use less capable cables.
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