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Displayport: A Better Video Interface

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Re: Displayport: A Better Video Interface

#81
post #74

Earlier quoted context omitted.

Technically macOS does support MST. But it only supports it to stitch together for a single display. It does not support daisy chaining two displays. Thankfully, every Mac for the last 7 years has Thunderbolt3 at least, so getting dual-4K-display from a single port/cable is still very doable, you just need a TB3 to dual DisplayPort or HDMI adapter.

Well except for some of the Apple Silicon machines. The M1 (and maybe M2?) only have two video output blocks, of which one is already used for the internal display. It’s honestly the biggest complaint I have about my M1 MBP. Yes DisplayLink or whatever it’s called exists but the performance is bad.

Ugh, right. Probably a freudian slip that I just mentally pretend those configs didn't come after half a decade of ubiquitous multi-display support on Macs.

Re: Displayport: A Better Video Interface

#82
"We’ve all gotten used to HDMI." Well that's it then, I don't need another less common way to do the same thing. There's always that theory that low-end devices will opt for DP to avoid royalties, but the cheapest laptops and monitors tend to be HDMI-only if anything because DP is more of a special feature.

Similar story with H.264/5 vs VP8/9.

Re: Displayport: A Better Video Interface

#83

Earlier quoted context omitted.

Sounds like an OS problem. When I do that it moves all open windows to the remaining display, but when I turn the other display back on it just moves them back. No special software installed for this, just stock macOS Ventura.

It's not an OS problem, that's how DP is supposed to work and that's in fact stupid

It’s an OS problem for not handling monitors being disconnected and reconnected properly.

What is stupid is having half your windows unreachable because they are on a monitor that is turned off. How does that help anyone?

Imagine how annoying it would be on a laptop? I use my laptop in a meeting, and have a few windows open on its screen, then I arrive at my desk and plug in my 2 external monitors and keep my laptop lid closed. Imagine if the windows on the laptop display stayed there, they would be unreachable and would have to manually move them to my other screens every time I moved from a meeting to my desk. Same for the other way around, I disconnect from my monitors and take my laptop to a meeting, and then I can’t access any of the dozens of windows I had open on my 2 external monitors.

That would be an absolutely brain dead way of working.

Re: Displayport: A Better Video Interface

#84
post #77

Are there any KVM switches that do Displayport well (i.e. where switching between inputs does not look like a display disconnect to the PC)? I'm still using HDMI because I like to share my home multi-monitor setup between my personal machine and my work laptop, and the KVM switches are able to fool the PCs into thinking the monitor are always connected. Years ago I tried a Displayport switch, but it could not -- I as…

https://store.level1techs.com/?category=Hardware

This is what I use. It appears to disconnect, but also doesnt seem to be an issue. My machines re-organize instantly.

Re: Displayport: A Better Video Interface

#85
post #59

I personally prefer HDMI or DVI, I don't like DisplayPort because on the display that I have, when I turn off the display the computer detects it as if I've physically disconnected the display, which then moves all the windows that I had open around and breaks my macros...

I /think/ this is related to the EDID support or configuration. What I do know is that you need specific EDID support when using a DisplayPort KVM because that switches the computer away on a regular basis. If you have multiple screens and a single screen KVM (fairly common) it will do the re-arrangement that you've experienced. With EDID support it keeps both output alive resulting in no re-arrangement. EDIT: It see…

> If you have multiple screens and a single screen KVM (fairly common) it will do the re-arrangement that you've experienced. With EDID support it keeps both output alive resulting in no re-arrangement.

Can you tell me some KVM switches that have a working implementation of that feature? I'm looking for one.

I'm still using a DVI KVM, because when I tried to upgrade to Displayport (years ago), I ran into the problem you describe and gave up.

Re: Displayport: A Better Video Interface

#86

With HDMI, I have both video and audio traveling over a single cable. That is _extremely_ convenient. DP _theoretically_ supports audio too, but AFAIK that's not widely implemented.

For some reason, outside of video, HDMI knows how to shoot themselves in the foot almost as well as the USB-IF. HDMI CEC? Has anyone actually got that working correctly? Anyone remember Ethernet over HDMI? Apparently that was a thing. (Not to be confused with HDMI over Ethernet, which actually has some uses.) HDMI for soundbars? We got ARC ports (Audio Return Channel). But it was buggy, didn't support lossless audio,…

CEC "just works" for me and has for as long as I've owned a flat panel TV (maybe 12 years or so?). Back in the day (before I had an HDMI receiver), I could use the TV remote to control the bluray player. These days I have a receiver, and the volume control on pretty much any device will control the audio on the receiver.

ARC was a bit more spotty, but I moved somewhere with no live TV reception, so my only use-case for it went away (everything else routes audio through the receiver).

Re: Displayport: A Better Video Interface

#87

With HDMI, I have both video and audio traveling over a single cable. That is _extremely_ convenient. DP _theoretically_ supports audio too, but AFAIK that's not widely implemented.

> That is _extremely_ convenient. I'm open to having my mind changed but I have not really experienced this extreme convenience in practice. The vast majority of things I plug a HDMI cable into either don't have speakers or if they do, the speakers are a bad quality afterthought. In actual fact, what has been an extreme inconvenience is the OS thinking I want HDMI audio instead of whatever much higher-quality* altern…

TV connection is a pretty big use case where audio matters.

Re: Displayport: A Better Video Interface

#88
post #84
post #77

Are there any KVM switches that do Displayport well (i.e. where switching between inputs does not look like a display disconnect to the PC)? I'm still using HDMI because I like to share my home multi-monitor setup between my personal machine and my work laptop, and the KVM switches are able to fool the PCs into thinking the monitor are always connected. Years ago I tried a Displayport switch, but it could not -- I as…

https://store.level1techs.com/?category=Hardware This is what I use. It appears to disconnect, but also doesnt seem to be an issue. My machines re-organize instantly.

It's gotten better in the last year or so with Windows 10 but it'll still sometimes just fall apart when the display configuration changes, which is something that just never happened for any reason with HDMI/DVI.

Re: Displayport: A Better Video Interface

#89

With HDMI, I have both video and audio traveling over a single cable. That is _extremely_ convenient. DP _theoretically_ supports audio too, but AFAIK that's not widely implemented.

> That is _extremely_ convenient. I'm open to having my mind changed but I have not really experienced this extreme convenience in practice. The vast majority of things I plug a HDMI cable into either don't have speakers or if they do, the speakers are a bad quality afterthought. In actual fact, what has been an extreme inconvenience is the OS thinking I want HDMI audio instead of whatever much higher-quality* altern…

I have an audio extractor that conveniently passes the sound from HDMI to my desktop speakers. The extractor is connected between my HDMI input switcher and the [primary] monitor, so whichever device I'm currently using outputs the audio to the speakers.

Re: Displayport: A Better Video Interface

#90
post #79

Earlier quoted context omitted.

If this were true, then people would be running datacenter networking over HDMI. Data is data - there is no benefit to designing two entirely different transport mechanisms for video vs other data. You could argue that video data has a deadline to meet - but ethernet already has lots of mechanisms for QoS and bandwidth reservations to make sure that someones torrents don't interrupt something latency sensitive. Sure,…

25 Gigabit Ethernet costs ~100x more than 32 Gigabit Displayport.

Sounds like the real question is why don't people use DP for p2p networking links...
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