Originally Posted by RobertR
I'm aware of "cable certification", but I've seen posts here on AVS that state people have tried "certified cables", and some of them have failed. So it appears that certification is a guarantee of nothing. I was just hoping there's a list of 25 ft. cables that are known to work based on independent testing, rather than a label.
A Premium High Speed HDMI cable is a copper-based cable that is tested and certified by an ATC (the program designed and approved by HDMI.org). Any cable mfr can have their cables tested by an ATC if they are willing to pay for the service. The testing protocols are standardized so regardless of the mfr and/or reseller, if it has the QR label (for authenticity) then you know it's been tested properly and reliably. The certification is only good to 25' and has recently been pushed to 30'. There are other factors involved besides the cable that will make for a successful cable run. That's why no one can give you a 100% guarantee that a cable, even certified, will work for any given setup. If all you're going to push is 4k and your run is under 25', then just about any well made cable will work (again depending on how it's installed). 4k HDR over about 20' will almost require one to use a hybrid fiber cable (Ruipro) because those are getting the most positive feedback from actual users here.
HDMI chipsets on your source/sink end, bend radius, switches, etc all play a part in a successful run. Any in-wall installation should be done with the use of a conduit (1.5" - 2.0") because that is the ONLY way to future proof your cabling because you will more than likely be swapping out cables again in the future.
Bottom line, cabling for 4k HDR over 20' is always going to be hit and miss to a certain degree, especially if you want to use copper-based cables. Hybrid fiber is what is most often recommended, but it's expensive. For 4k HDR under 25', then just go with an ATC certified cable because that will give you the best chance of success, but won't be a guaranteed success for the reasons I gave.