HDMI cables are crap

Speednut357 · Jan 2, 2024

I have had two issues now related to fake HDMI cables. If a cable is not HDMI 2.0 compliant, it will fail to pass the required bandwidth. Symptoms are A blinking display and white or green dots on the display. This problem is caused by crap suppliers naming their products as HDMI 2.0 when actually it's just old stock they are trying to sell. It really sux.
Try to use Displayport wherever possible, and if you have problems using HDMI cables, try changing them. Keeping the cable as short as possible is also a good idea.

CRnSC · Jan 22, 2024

Also... depending on your monitor, DisplayPort (DP) will usually allow higher refresh rates and can better support widescreen ratios.

Now, DP has the same issues with higher version numbers equals higher data rates. Try to get both a monitor and a video card that support DP ver. 2.0 or higher (I think they just came out with DP2.1).

As far as HDMI-- and DP cables as well... buy a lot of cheap ones or one really good one. It doesn't have to cost $70US, see if you can get a deal on a brand name... check places like Monoprice and Cables2Go (not an endorsement, just suggestions).

Botmeister · Jan 23, 2024

Not claiming you didn't check everything! But many things can have effect. DP is indeed better, but HDMI also does the job within its limits

To understand the situation, you would need to provide exact details. GPU, resolutions, ports used on both endpoints, multiple monitors, Window settings, amplifier ARC throughput.... and the list goes on.

HDMI does an EDID handshake. When two endpoints are connected, let's say your GPU and your ultrawide monitor, both devices tell each other what is the max resolution we are going to operate on, And things like HDR on/off etc. This affects the bandwith and thus the max throughput of the cable.

If the 2 endpoints fail the handshake, then you would get no image at all (or maybe very low res). Issues you're having are green/white dots and flickering image. My guess it that it's gpu related, not cable. Or maybe cable not plugged in properly. Or HDR might be switched on in one of the endpoints. Or the monitor-menu settings have been put on overclock mode in combination with motion blur on/off..... Windows settings and your monitor-menu work together, they affect each other directly.