DP has a HDMI compatibility mode that allows a DP output to output a HDMI signal, but at the wrong voltage. The external adapters are just level shifters to bring the signal voltages into compliance with HDMI, but their entirety passive devices.

> Even the PS4 had a DP > HDMI adapter internally for some reason.

DP is far more than just an external display protocol. Its biggest use case is internal display signals, so it’s used to power pretty much every laptop screen.

As a result standard PC hardware (which is what the PS4 is) has defacto support for DP, because is the standard display transport between embedded video components. As a result it’s a lot easier and cheaper to build a device that outputs DP, and then slap a HDMI converter on it, than it is to build a device that uses HDMI natively.

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felurx 5 days ago | parent [-]

> DP has a HDMI compatibility mode that allows a DP output to output a HDMI signal, but at the wrong voltage. The external adapters are just level shifters to bring the signal voltages into compliance with HDMI, but their entirety passive devices.

That's DP++, which is not supported on all DP outputs, and notably is not supported by the USB-C DP AltMode.

	▲	ThatPlayer 4 days ago \| parent [-]
		DP++ seemed to work fine on my Samsung S24 phone when I tried it after seeing that comment and was curious. I've got a pile of passive adapters because I have an esoteric device that has broken DP audio but HDMI audio using DP++ works fine.