[arghwhat]

There's a lot of misunderstandings about USB PD communication, in particular Vendor Defined Messages. The LTT video kept making this mistake, and mixing in misunderstandings around messages to the eMarker chip itself (SOP'). It was a painful watch.

Vendor Defined Messages have is part of any normal PD exchange, as they're simply anything that isn't defined by the PD spec itself. You'll see VDMs when connecting any device supporting more than just dumb charging, as it's used for all sorts of things like DisplayPort, Thunderbolt, eMarker identification, etc. - stuff we'd expect ehre.

The quote from Antak refers to just a single, possibly/likely proprietary, message. This could be to ID the dock on the basis of e.g. rejecting the switch 1 dock should one cram it in, or to reject switch 1 dongles. Maybe it's Nintendo speak for "dock capabilities: cooling", with the switch having no mode for docked gaming with reduced performance without cooling.

Intentional incompatibility, yes, but it's 1 message of an unknown type within bog standard USB-PD, not a "vendor defined lanugage" or "over 30 proprietary messages".

[grishka]

Why reject switch 1 accessories though? Sure the video resolution will have to be limited to 1080p, but that's kinda expected and I'm sure switch 2 can do that anyway

[arghwhat]

Switch currently runs in one of two modes: Docked and handheld. Games are written to expect those two modes, with rendering adjusted to those specifically and nothing else. Think of all the render settings in a PC game (in reality there are way more things the developer can adjust, but just for the sake of illustration), and assume there are instead two hardcoded presets which are selected based on whether or not the device is "docked".

For Switch 1 games, docked means "we're running as fast as the internal cooling can handle and outputting 1080p, assume the user can't use the touch screen and such". A dongle is fine here as long as you don't block the air inlets or exhausts, or place the Switch on something heat sensitive.

For Switch 2 games, docked means "we're running as fast as the externally boosted cooling can handle and cranking out 4k, and assume you can't use the touch screen and such". Assuming the fan does useful work here, then with a dongle you'll be thermal throttling and have a bad gaming experience - on a PC you'd turn down the settings, here those are hardcoded.

So, what about using the switch 2 handheld mode on a switch 1 dock, seeing it's the same resolution? Well, if you tell it to run in handheld mode it might assume you have access to the touchscreen, always-on VRR and HDR, is using internal speakers, etc.

It's totally doable, but to do this right the stack needs to be prepared for it. As such, I understand why they did it.

Heck, this was the same issue for the Switch 1, and it took a while for third-party docks to pop up. It'll take all but a moment for third party docks to support this.

[grishka]

Ah so the Switch 2 dock has an extra fan? I didn't know that.

Still, what happens if you connect a Switch 2 to a 1080p display? I assume it would render at 1080p, because rendering at 4K and downscaling for output would be too wasteful. Switch 1 even has a setting for that, allowing you to choose between 480p, 720p, and 1080p.

[naikrovek]

It renders at 1080p and the dock doesn't get as hot.

Note that the cooling fan inside the dock is for cooling the dock and not the Switch 2 itself. The Switch 2 has its own fan for that.

So while not everyone docks the Switch 2 to a 4K display, the Switch 2 dock must support that.

[mathiaspoint]

DP -> HDMI conversion hardware is pretty intense. I haven't owned a device that does this and doesn't at least get warm.

[naikrovek]

> DP -> HDMI conversion hardware is pretty intense.

It can be, but it doesn't have to be. DisplayPort is mostly a superset of HDMI, with different voltage levels. Going from HDMI to DisplayPort is much harder than going from DisplayPort to HDMI, though the hardware to do this is apparently much cheaper than it used to be, which is nice to see.

DisplayPort to HDMI only requires level shifting, as I understand it. I'm sure someone will correct me if they see this and I'm wrong.

[arghwhat]

It's not. Every USB-C to HDMI cable in existence is a DisplayPort alt-mode cable with a DP to HDMI converter at the end. They don't require active cooling, even if they get a little warm.

[naikrovek]

> Why reject switch 1 accessories though?

Because the Switch 2 is a different machine. Games being backwards compatible (via emulation) doesn't mean the hardware is (or has to be) backwards compatible. Different display chips, different display protocols, etc.

People made all kinds of claims about how the Switch 1 wasn't USB Type-C compliant when it was discovered that the Nyko dock kept frying the power management IC in the first Switch console. I think a lot of that false communal knowledge has carried forth to the Switch 2, unfortunately.