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cassianoleal a day ago

An adaptor costs £7.

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AnthonBerg a day ago | parent | next [-]

They are not equivalent.

Conversion is a very intricate spec fulfilment over an incredibly high bandwidth signal.

I did the dive; The adapters are not sufficient.

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whazor a day ago | parent | next [-]

Do you know whether HDMI CEC adapters impact the signal?

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perching_aix a day ago | parent | prev [-]

In what way are they not sufficient?

	▲	charleslmunger a day ago \| parent [-]
		The Synaptics VMM7100-based adapters only support VRR on older firmware versions with bugs. The Chrontel CH7218 is the most reliable but still also suffers blackouts during VRR. ParadeTech PS196 adapters advertise VRR support but their DPCD does not correctly communicate that it is supported. So even if you add the chip to the VRR PCON list in the amdgpu driver, it still won't see VRR as supported. And while some of these advertise themselves as displayport 2.0, all of them only support bandwidth of 25.96gbps on the displayport side, requiring DSC for 4k 120hz 10bit color, even though they support 48gbps on the HDMI output.

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tapoxi a day ago | parent | prev | next [-]

For HDMI 2.0. For HDMI 2.1 and 4K/120hz you're looking at north of $25 and don't get VRR support.

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cassianoleal a day ago | parent [-]

Fair enough about VRR, but £13 for 4k/240Hz - https://www.amazon.co.uk/dp/B0FQCF62CD

	▲	elabajaba 16 hours ago \| parent \| next [-]
		I've owned 2 of these (returned and reordered thinking the first might've just been bad) and neither worked properly on Linux with an AMD 9070xt and an LG CX. They'd have black screen dropouts every few minutes, and occasionally full screen color corruption.
	▲	redeeman a day ago \| parent \| prev [-]
		with lossy compression

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amlib a day ago | parent | prev | next [-]

They have limitations, specially when driven to the limits of the specifications.

When doing 4k@120fps 4:4:4 chroma you might have to deal with longer handshakes and sometimes even no handshake at all. Or random dropouts. Or HDR not activating properly.

	▲	happyPersonR a day ago \| parent [-]
		I thought handshakes were just when you were setting up a connection no? Random dropouts tho sound bad… with high speed signaling also sounds like a pain to figure out

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eliaspro a day ago | parent | prev | next [-]

But wouldn't this break the HDCP chain and therefore render many use-cases (playback of DRM-protected streams) broken?

	▲	cassianoleal a day ago \| parent [-]
		Is that a problem for most uses of DP?

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preisschild a day ago | parent | prev [-]

There are only a few adapters that support the 2.1 features (hdr+vrr+high resolution+high refresh rate, no lossy DSC). I even had to flash custom firmware for most of those features to work (vrr still doesnt)