weaveworld said:
SvennoJ said:
Will I need to buy new HDMI 2.0 cables?
That depends. You can use your existing HDMI cables with new HDMI 2.0 connections as the connectors themselves haven't changed. While there's no such thing as an HDMI 2.0 cable per se, displaying 4K at 50/60Hz will require a High Speed/Category 2 HDMI cable. You can pick one up for a few pounds/dollars online. Don't spend any more.
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First of all many thanks for linking but all that stuff i have read on plenty of different sites already and thats why i came to ask here. It might be my lack of comprehensive skills but i am still confused. Or maybe more annoyed by the way sites are describing this issue.
I have 4 cables and they all say 'high speed' but not one has it mentioned wether they run at 18Gbps or less. Nor any mention of 1.4 or 2.0. These are all cables bought in the past 2 years from different retailers and different quality varying in prize from 4 euro's to 20 euro's. Now retailers do advertise with 2.0 cables which seems to be bullshit because it isn't a change in cable or connector from what all these informed sites tell you but in the same sentence they mention the 'new' standard for running 4k at 60hz... For which you would need 2.0 cables???
Am I this stupid I ask of you...
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To get technical it all depends on signal to noise ratio of the physical wires inside the cable. It's not so simple as 1's and 0's flying through the cable. Quality of materials and shielding effects the signal and due to interference the signal arrives more like 0.7 - 0.3 ish at the other end (over simplification) The higher the speed you try to push signals through the cable, the shorter the pulses, the bigger the effect of interference and signal degradation.
This is what the signal looks like travelling through your cable
1080i left, 1080p right. The longer the cable, the higher the speed, and depending on materials, the 'eye' in the middle separating the signals will get smaller and smaller until the signal corrupts. http://www.hdmi.org/installers/eyediagram.aspx
Very detailed explanation: http://www.onsemi.com/pub_link/Collateral/AND9075-D.PDF (Uderstanding data eye diagrams)
So yes, all the cables have the same capabilities. The speed rating guarantees that the cable has been tested to be able to run at that speed with sufficient signal to noise ratio that it should never drop any bits. That doesn't mean that a cable tested for slower speeds isn't physically good enough to run at a higher speed.
If the signal to noise ratio isn't good enough, the receiving end will start interpreting the 1's and 0's wrong, which is immediately visible as no signal at all or image corruption. It's not like analog where you get a slightly worse looking picture, it's either pristine or full of corrupted lines. So it's not complete bullshit, the 2.0 speed rating simply means the cable has been tested to run at 18 Gbps.
Hdmi 2.0 ports have some tricks up its sleeve to improve the signal quality as well, so it's not as easy to say that an older cable won't be good enough.
https://www.synopsys.com/Company/Publications/SynopsysInsight/Pages/Art3-hdmi-2.0-IssQ3-13.aspx?cmp=Insight-I3-2013-Art3
The only way to know for sure it to simply test the cable.
