Question 4k@120Hz flickering

[gabecz]

Hi
RTX3070 and 65QN90D TV here. I so far have found only one cable in the house (I have boxes full of them) that wants to let me go up to 120Hz, and even that flickers every now and then. And flickering I mean colors shift and back within a fraction of a second.
Is that because the cable is not 4k120hz ready? The sign on it says High Speed not Ultra High Speed. not too long though. Are those 20ft long cables claiming to be able to handle 120Hz on 4k true/real? I'd prefer not to spend more than 20 bucks on the cable to be honest.
Any suggestions? I have seen "fancy" / quality looking ones for $25-$27 dollars. Which if you all say is the one I need I'm ready to buy.
Thanks for suggestions

 

[beyondlogic]

Hi
RTX3070 and 65QN90D TV here. I so far have found only one cable in the house (I have boxes full of them) that wants to let me go up to 120Hz, and even that flickers every now and then. And flickering I mean colors shift and back within a fraction of a second.
Is that because the cable is not 4k120hz ready? The sign on it says High Speed not Ultra High Speed. not too long though. Are those 20ft long cables claiming to be able to handle 120Hz on 4k true/real? I'd prefer not to spend more than 20 bucks on the cable to be honest.
Any suggestions? I have seen "fancy" / quality looking ones for $25-$27 dollars. Which if you all say is the one I need I'm ready to buy.
Thanks for suggestions

View: https://www.youtube.com/watch?v=clvAs9FEg_g


try diagnosing with this youtube video also check other hdmi slots on back as it may be a dodgy hdmi

 

[Glenwing]

High Speed HDMI is not tested up to those speeds.

 

[gamerk316]

You don't need a "high quality" cable; you just need one rated for the specified bandwidth. Just purchase an Ultra High Speed cable from Monoprice and call it a day.

 

[boju]

I think 3m would be maximum you'd want to run for 4k 120Hz. Amplified/active cables to go longer but these will be pricey.

Monoprice as said above or the cable (3m) im using by Cruxtec running 4k 120Hz on LG C1, that was $30 aud.

Ultra high speed / Hdmi 2.1 cable.

 

[gabecz]

for now i'm having a shorter not even ultra high speed cable and place the pc next to the tv when playing and back to its place when not.. free workout

 

[SyCoREAPER]

Since you bumped yourself, you can avoid active cables by going fiber. Only downside is most affordable ones are directional which in your case wouldnt be an issue, only with AVRs using (e)ARC.

A good, shielded traditional HDMI 2.0b cable might get you all the way with 4K@120 4:4:4 but it's pushing the absolute limit at 20 feet and would probably need to drop down to 4:2:0 which won't look good or correct.

If what you're doing now works and isn't a huge issue, keep doing that. Otherwise I'd recommend fiber HDMI for longer stretches.