HDIM (eARC) 2.1 4K port vs HDMI 2.1 4K: What is the difference?

[Cannibal Corpse]

Hello all,
My new Sony A80K has TWO 2.1 ports:

HDM1I 3 (eARC) 4K 120Hz
HDMI 4 (non eARC) 4K 120Hz

And two regular (non 2.1) 4K ports:
HDMI 1
HDMI 2

Questions:

1) My PS5 used to be connected to HDMI 3 (eARC) 4K 120Hz, but I decided to connected to HDMI 4 (4K 120Hz, non eARC) port instead (I will give the reason shortly below):
Do I loose any image fidelity on my PS5 by this recent switch?

2) The reason I did this switch is the following: my main gaming system which has a RTX 3060Ti, simply displays garbled image (most of the time) if I connect to HDMI 4 (non eARC) 4K 120Hz port.

I just fixed the issue, by simply using HDMI 3 (eARC) 4K 120Hz port instead. It simply works, and no more garbled image.
Why 3060Ti refused to work on non-eARC port?

 

[kirbyrj]

It should have no difference as the eARC is about audio.

https://www.hdmi.org/spec21sub/enhancedaudioreturnchannel

 

[Cannibal Corpse]

Thanks, I am just curious as to why the 3060Ti would produce garbled image on non eARC port however. See my other post here: (I recently replaced my EVGA 2080 Super with this RTX 3060Ti)

https://hardforum.com/threads/rtx-2080-super-vs-3060ti-oem.2023525/