Yep, I've looked at DP/MST mode for a while now, but either linux support was rather limited, or gpu support was limited when I needed it prior. Plus your link says MST is good for 24Gbps throughput, which is about enough for only 1 4k 4:4:4 signal (18Gbps), even 4k/30 comes in at 10.2Gbps so only 2 (theoretically might work, I can live with 30hz). The active DP might be worth looking at again, that one was only 30hz though, which tends to be some of the problem, I couldn't find any full 4:4:4 that weren't really expensive. Bit hard to get full signal out of some of these Chinese crap gadgets. I did look closer at the cheap EDID adapters Brian sent, and looking at like models a few specifically state "not compatible with DP to HDMI adapters", which is exactly my scenario. I learned trying to use dp-to-hdmi adapters with "active" thin hdmi cables did not work, and no other active translation seems supported with more than one, including these sadly. I think you're both probably right, I'd need to use something like a set of active devices across them, if they even make a DP in and full 4:4:4 HDMI out adapter as an active, intelligent translator device. It's an old pain, but talking about it again has me interested enough I'll shop around and see what I can find that can spit out a full 4k signal these days. Thanks for the good tips to consider! -mb On Mon, Aug 24, 2020 at 8:57 AM Stephen Partington via PLUG-discuss < plug-discuss@lists.phxlinux.org> wrote: > Did you ever try/consider something like this. Displayport to multiple > HDMI out? > > > https://www.amazon.com/StarTech-com-DisplayPort-HDMI-Multi-Monitor-Splitter/dp/B015J8Q6ZK (many > options here. not al lare create even remotely equal...) > > And the active DP->HDMI costs have come way down. (This may be what you > need for it all to play nice) > https://www.amazon.com/dp/B07D2HSH4D/ > > > On Mon, Aug 24, 2020 at 7:23 AM Michael Butash via PLUG-discuss < > plug-discuss@lists.phxlinux.org> wrote: > >> > others cheap geeks wanting to use a big tv too> >> >> You're right, the ports on the dock are DP1.2, but the TV is HDMI2.0, so >> using an all-in-1 DP-to-HDMI cable, presumably the dongle chip built into >> it, but hopefully better being "built in" together than a separate >> DP-to-HDMI dongle+cable. >> >> Even using matched dongles and cables had recurring issues, similar to >> Linus Tech Tips on youtube using an 8k TV, that required literally 4x HDMI >> connections to use the 8k setup, and none would sync with each other. >> Using a combo DP-to-HDMI cable resolved this (provided by the TV vendor of >> course), but dongle+cable was a no-go. >> >> I've done a fair amount of diag watching the display churn during >> power-down, no signal, etc and per xrandr it's typically showing the >> correct display modes, and presence of the display (while in power down, >> but os seems to know it's not active to use it). KDE, which when it isn't >> infuriating me, tends to be what I use, and it just always does a horrible >> job of shifting windows, display settings, refresh/resolution, etc during >> these transitions of all/some displays at once. It's not only KDE though, >> Cinnamon, Mate do it too, seems a systemic issue outside the DE. Plus it >> happens with either Intel or Nvidia, so that leaves me staring at the >> kernel, or xorg itself being quirky. >> >> I think you're right with a static edid and a device to do it, I've >> considered this in the past with some of the magic video adapters that do >> this for various odd devices, but were expensive for adapters when I need >> 2-3 of them (they were over $100ea last I looked). These little single >> shot static units might work if I can find one for HDMI-to-HDMI. >> >> However my fear is the problem is more with the DP to HDMI chip that is >> translating, either in a dongle or built into a cable, which I think is >> where things get flaky (since I have to still "reboot" them occasionally >> with a cable pull. If that is glitching, I don't think a static edid >> adapter would even help at the hdmi end as I think the issue is more at the >> DP and adapter side. >> >> Native HDMi ports would probably work, but no one makes a multi-HDMI card >> or dock I've found, at least not for 4k/60 x2 or 3 displays. The docks I >> did find were typically DisplayLink chip-based docks, which make crappy >> usb-to-video chips with dubious linux driver support, particularly anything >> not already 3-4 years old. DisplayLink has always been Linux-unfriendly, >> and just not something I'll bother with. >> >> Nothing is ever perfect.... >> >> -mb >> >> >> On Mon, Aug 24, 2020 at 4:48 AM Brian Cluff wrote: >> >>> If all your connections all end up plugging into the HDMI port of the >>> TV. You should be able to just plug the EDID device directly into the TV >>> and your HDMI cable into it and it should solve all your problems... Unless >>> I've missunderstood and you have found some TVs with displayport >>> connections on them. >>> >>> Brian >>> >>> On 8/23/20 7:00 PM, Michael Butash wrote: >>> >>> That looks pretty cool, but my dock is 1x TB3 in, and 2x DP1.2 out on >>> there, so really the problem is adapting DP1.2 to HDMI there to 2 of the >>> displays. My third display mostly sees playstation activities these days >>> until I screw around with my failed desktop, but still use 2x TV's with my >>> built-in 4k laptop display as 3rd. >>> >>> I used to use a separate hdmi cable and a DP-to-HDMI adapter, but >>> randomly saw someone else having issues with them (particularly with 8k >>> displays muxing across them), then got an integrated DP-to-HDMI cable I had >>> better hope for (could not find his exact brand). It's a bit better, but >>> still occasionally requires reseating. I suspect this is a bug in the >>> hardware/firmware on the adapter soc, but who knows. >>> >>> Maybe what I need is one of those adapters for more hdmi-to-hdmi at the >>> tv end, or DP-to-DP for the same at the dock end. I'll look around see if >>> something like what you sent me. >>> >>> Appreciate you look around on this for me, I have really odd issues no >>> one ever else much seems to. Perhaps self-inflicted gunshot wounds, but I >>> like to think I'm pushing boundaries. ;) >>> >>> -mb >>> >>> >>> On Sat, Aug 22, 2020 at 10:41 AM Brian Cluff wrote: >>> >>>> I think I've found the solution to your display problems, you just need >>>> to buy a 3 pack of these (relatively inexpensive): >>>> >>>> https://www.amazon.com/FUERAN-stabilizer-Thunderbolt-fit-Headless-4k-3840x2160/dp/B07ZYLGDK3 >>>> >>>> Just read the reviews. It sounds like it solves your exact problem. >>>> The reviews also say that it can be used with a displayport to HDMI adapter >>>> unlike what the product description says. The product has a lot of >>>> chinglish in it so I think what they mean is that it's not a displayport to >>>> hdmi adapter. >>>> https://www.amazon.com/product-reviews/B07ZYLGDK3/ref=acr_dp_hist_5 >>>> >>>> It appears you need to purchase the correct device for the resolution >>>> you want to run and then once plugged in it just tells the system that >>>> there is a display connect all the time, even if it's turned off or there >>>> isn't one plugged in at all. This is the device that I was mistakenly >>>> calling a DPMS proxy in my previous message. I had forgotten that it's >>>> actually an EDID proxy, and they are a lot cheaper than when I was trying >>>> to solve my similar problems in the past. >>>> >>>> I hope this helps... >>>> >>>> Brian Cluff >>>> >>>> >>>> >>>> On 8/22/20 8:30 AM, Michael Butash wrote: >>>> >>>> All valid points and correct Brian, cost vs. function. ~3yr ago when I >>>> bought these displays, I was moving from 6x 24" ancient dell lcd's, and got >>>> a "good" deal on these for about $650ea, curved samsung 48" 4k/60 >>>> displays. Couldn't get close to that with a real large monitor, let alone >>>> curved (great for my desk) and in fact really couldn't find any period >>>> except some off-brand chinese ones I expect to last no more than a year. >>>> >>>> I'd purchased a CEC injector to play with, but kind of a pain to run >>>> and sync 3 of them at once, plus ~$50ea. Was going to try a rs232 adapter >>>> on a quad serial adapter, but eventually realized I can live with shutting >>>> off the displays manually via good old remote. >>>> >>>> The problem comes in doing so, you can't really catch and power-down >>>> all at once, which causes video subsystem to start resizing from 3 >>>> displays, to 2, to 1, then none, which pretty much freaks out KDE and other >>>> DE's. KDE has been notoriously horrible about multi-monitor support over >>>> the years, window placement/size preservation, random resolution setting >>>> resets, things like that. Now add in some dongles that randomly require a >>>> physical disconnect to resume proper function randomly, every day, >>>> sometimes multiple times a day if I have power management shutting down >>>> displays, and it gets infuriating rather quickly. This was on my desktop >>>> with a dedicated video card even! >>>> >>>> Now I'm using my laptop and the TB3 dock, which I find if I simply walk >>>> up and yank the dock TB3 connector, so all external displays drop at once, >>>> then power them down, they actually work fairly normally. I have to >>>> disable power down of displays, but since the tv's won't shut off entirely >>>> anyways, isn't that big a deal, other than the constant heat these generate >>>> and my failing old AC in the house. >>>> >>>> I'm a bit more surprised HDMI still this day doesn't support DPMS-type >>>> functions to some extent, even if "legacy" vs. only CEC. Likewise I'm >>>> surprised companies like samsung don't just include a DP port on their TV's >>>> too, as it's more common to see folks like yourself and I using TV's as >>>> displays, as most tv's are better quality and price than any available >>>> "computer monitor" unless you need/want 144mhz gaming refreshes (that your >>>> eyeballs can't see anyways). >>>> >>>> I figure at some point a developer might buy a few of these tv's and >>>> realize how asinine this all is to use to resolve it, but considering here >>>> we are in 2020 and my first reports of some of this stuff began a decade or >>>> more ago, perhaps not. KDE is still working on trying to fix window >>>> placement a decade or two on, seeing this just today... >>>> >>>> >>>> -mb >>>> >>>> >>>> On Fri, Aug 21, 2020 at 10:16 PM Brian Cluff via PLUG-discuss < >>>> plug-discuss@lists.phxlinux.org> wrote: >>>> >>>>> The problem with your setup is that you're using TVs for multiple >>>>> displays. Like you said, TV's don't understand DPMS so it's impossible to >>>>> get them to power down on command. Most newer TVs do understand CEC and >>>>> it's possible to get a CEC injector (I believe NVIDIA doesn't handle it in >>>>> their cards) to send a signal for the TV to power itself off/on when you >>>>> want it to. The biggest problem is that when TVs turn off, they stop,for >>>>> the most part, reporting on the cable that they are there, so from the >>>>> point of view of your system, you are unplugging and plugging in the TV's >>>>> from the system, probably in some random order, and the system has to >>>>> quickly deal with handing changing scenarios of one monitor configuration >>>>> after another as the TVs turn on... It's probably freaks out because it's >>>>> asked to setup a display on one TV.... no wait 2 TVs... Just kidding 3 >>>>> TVs... but it's still trying to handle the first one by the time it's asked >>>>> to handle the 3rd one. I have a feeling that TV's also don't have the >>>>> unique ID's that monitors have so it will also struggle to automatically >>>>> place them back in the correct order once they are all up and running if >>>>> you are using the same model TVs for all your displays. >>>>> >>>>> I personally use a single 50" 4K display for my desktop and other than >>>>> having to turn it on and off by hand, it has worked flawlessly for the past >>>>> 5 or 6 years... but then again, I'm only using the one TV for my display. >>>>> Before that I used a 3 monitor setup, with actual computer monitors and I >>>>> didn't have any problems at all with that. My brother had a system with I >>>>> believe 16 computer monitors and that worked very well as well, but again >>>>> that were actual monitors. >>>>> >>>>> I think I remember coming across a device that was a DPMS proxy that >>>>> might fix your problem. It basically sits between you computer and display >>>>> and fakes a monitor signal to your computer so that your TVs don't appear >>>>> to be disappearing and reappear to your computer constantly. >>>>> >>>>> You could also hard code your display setup in your Xorg.conf so that >>>>> it would have no choice but to setup your display like you like it, but >>>>> that could make things difficult/stange for you at a later date if you ever >>>>> change your display setup. >>>>> >>>>> Or, you could always get real computer monitors, but that would be >>>>> very expensive which is probably why your using TVs in the first place. >>>>> >>>>> Brian >>>>> >>>>> On 8/20/20 5:25 PM, Michael Butash via PLUG-discuss wrote: >>>>> >>>>> I have had lots of issues with video and adapters the past few years, >>>>> mostly as I'm forced to use them. My nvidia 1070 in my desktop has 3x >>>>> DP1.2 ports and 1 HDMI2.0. I have 3 displays, so I use the 3x DP1.2 ports, >>>>> and run those through adapters to HDMI2.0 on my Samsung TV's I use for >>>>> monitors. Non-stop chaos ensues during power-down and up every day, >>>>> something different, every linux desktop hates it. Often one display or >>>>> another will freak out, and I end up; having to hard disconnect the adapter >>>>> (ie, reboot it) to work again or it'll come up stuck in 768x1024 (on a 48" >>>>> tv...). >>>>> >>>>> I found HDMI doesn't handle DPMS sort of power-off modes as vga, dvi, >>>>> dp, or most methods of displays to handle soft power-off scenarios, ala >>>>> just power down displays. When my laptop powers them down, they remain on >>>>> with no signal, which seems to just confuse the video card and adapter that >>>>> both freak out. This seems to have a profound effect on displaya and video >>>>> cards that don't realize most displays are now hdmi... >>>>> >>>>> Graphic subsystems are a basketcase these days under linux, mostly >>>>> because of these damn adapters, dongles >>>>> , and vendor wars. >>>>> Intel, that wants to sell all the things, including the most useless gpu on >>>>> the earth, injects themselves into everything, and always cause me issues >>>>> as I can't convince the os to use the (real) nvidia gpu. Probably the same >>>>> sort of issue if an intel gpu is around with AMD. Last I used an AMD GPU >>>>> some 4-5 years ago, it was an issue. Nvidia Prime via Intel is still >>>>> sketchy af. >>>>> >>>>> Even on a dedicated nvidia gpu in a server-ish xeon system, with >>>>> DP-to-whatever adapters I had nothing but issues. My latest iteration is >>>>> my laptop (xps 9560) and a thunderbolt3/usb-c dock with 2x 4k/60hz outputs >>>>> via one-piece DP-to-HDMI cables. I still have quirks, but I've learned to >>>>> work around, and now somewhat understand really odd hardware behaviour >>>>> enough to reproduce it. Occasionally I still need to disconnect a display >>>>> at the DP-to-HDMI cable I use now, which is again oddly random. >>>>> >>>>> I don't like the adapters, but my 48" TV's I use for displays don't >>>>> often come with DP ports native, and using HDMI comes with power management >>>>> oddities. A lot depends on your cabling and even display these days. >>>>> >>>>> -mb >>>>> >>>>> >>>>> On Wed, Aug 19, 2020 at 1:05 PM Seabass via PLUG-discuss < >>>>> plug-discuss@lists.phxlinux.org> wrote: >>>>> >>>>>> No, on the desired monitor, it still black screens. >>>>>> >>>>>> Works just fine (Even without that parameter) on something that has a >>>>>> direct HDMI cable, though. (TV) >>>>>> >>>>>> > Message: 6 >>>>>> >Date: Tue, 18 Aug 2020 16:23:47 -0700 >>>>>> > From: Aaron Jones >>>>>> > To: plugaz@codezilla.xyz, Main PLUG discussion list >>>>>> > >>>>>> >Subject: Re: KMS but AMDGPU And Black Screen >>>>>> > Message-ID: <6B7D5942-0F2F-4DAE-A54A-19215718DCF2@gmail.com> >>>>>> > Content-Type: text/plain; charset="utf-8" >>>>>> > >>>>>> > https://bugzilla.redhat.com/show_bug.cgi?id=1594488 >>>>>> > >>>>>> > Set amdgpu.dc=0 in bios and it will work but without hdmi sound. >>>>>> --------------------------------------------------- >>>>>> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>>>>> To subscribe, unsubscribe, or to change your mail settings: >>>>>> https://lists.phxlinux.org/mailman/listinfo/plug-discuss >>>>> >>>>> >>>>> --------------------------------------------------- >>>>> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>>>> To subscribe, unsubscribe, or to change your mail settings:https://lists.phxlinux.org/mailman/listinfo/plug-discuss >>>>> >>>>> >>>>> --------------------------------------------------- >>>>> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>>>> To subscribe, unsubscribe, or to change your mail settings: >>>>> https://lists.phxlinux.org/mailman/listinfo/plug-discuss >>>> >>>> >>>> >>> --------------------------------------------------- >> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >> To subscribe, unsubscribe, or to change your mail settings: >> https://lists.phxlinux.org/mailman/listinfo/plug-discuss > > > > -- > A mouse trap, placed on top of your alarm clock, will prevent you from > rolling over and going back to sleep after you hit the snooze button. > > Stephen > > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org > To subscribe, unsubscribe, or to change your mail settings: > https://lists.phxlinux.org/mailman/listinfo/plug-discuss