Trying to connect external VGA monitor freezes and breaks everything (needs reboot). Confirmed works on same computer with another distro (MX-Linux). Maybe radeon driver problems? KDE plasma Xsession. Old "Thinkpad E525" laptop

dwawlyn · July 13, 2023, 9:36pm

(
I just booted into another distro on the same computer (an MX-Linux live-usb)
and confirmed that it works fine there.
)

So I tried to plug in a VGA external monitor to my old “Thinkpad E525” laptop running opensuse tumbleweed,
and nothing happened at first.

I’m using KDE plasma, so I tried looking at its “Display Configuration” settings
(ie the GUI that pops open from this shell command: $systemsettings kcm_kscreen)
but there were no relevant options/info displayed there.

So after waiting a while and still nothing happening,
I popped open a terminal and entered xrandr --query just to see…
and everything immediately froze up and broke.

Well, mostly froze
– the window that was drawn on the screen persisted, frozen,
but I was still able to move my mouse pointer
(
and the mouse pointer seemed to change appopriately to what I was trying to do
– eg, changing from a text-insert “I” to a normal arrow-pointer when I blindly alt-tabbed (I think) between windows which I think held text/clickable elements.
)

I could reach the tty’s (ctrl-alt-F1,F2,F3,F4,F5,F6)
(
Oddly, I only have those 6 tty’s (F1 to F6), and my Xsession is on tty2 rather than tty7.
Is that normal for opensuse?
The Xsession being on tty2 isn’t maybe an indication something is weird with my system, right?
It persists after reboot…
)

(And of course the "magic “SysRq-alt-REISUB” sequence still worked to reboot.)

I tried it again, with similar results
– but not exactly the same
– eg, at one point, I saw the OSD icons for selecting between the mirrored-vs-extended etc options.
But then the screen froze up on that instead.

[
EDIT: to be clear, the pattern is (from 2 or 3 or maybe 4 tries)
I plug in the monitor,
and nothing happens at all,
until I just query xrandr
(not even setting anything)
and then everything immediately breaks.
]

The only time I got anything to display clearly on the external monitor was to one of the tty’s,
I saw this error message that seems to be about radeon drivers?
[this:]

Meanwhile the in-laptop display was flashing garbage
(like scrambled squiggly lines. Took a vid, but can’t upload vids).

On trying to go back to the Xsession after that,
the output switched back to the in-laptop display,
and I saw a different frozen screen,
with a rectangle of pastel-color-smudges (that I would guess was the desktop wallpaper trying to render for the external screen?)
and the KDE “Display Configuration” showing a confirmation message:

“A new output has been added. Settings have been reloaded.”

[this:]

So it got that far at least,
but of course everything was still frozen and I had to reboot again.

(
The starting resolution of the in-laptop display is the same on MX-Linux and opensuse
– 1366x768
and I think on opensuse it’s trying to apply the same resolution to the external monitor as on MX-Linux
– 1680x1050

)

(
… sorry, I’ve been up like… over 24 hours now, chasing cascading series of hardware failures on a separate computer
(finally determined it’s pretty much completely dead),
and this external display problem is majorly hampering my use of my opensuse computer to fill in for that lack,
and maybe this whole post is babbling nonsense,
but I’m just gonna post it now,
and maybe when I wake up I’ll get lucky and find some helpful response that at least means I have one problem less to grind through figuring out how to… not even really fix at this point, just deal with…
)

mrmazda · July 14, 2023, 12:07am

That’s a lot of words that say little that’s useful, such as Old Thinkpad. When having stuttering, locking up or other display problems, it’s the specific GPU(s) that matters. That information is usually best provided via inxi -GSaz run in Konsole, and pasted here using PRE tags, the #6 icon, above the input window just left of icon row center.

Upstream recently hijacked tty2 for Plasma to run on, and IIRC, that’s also where SDDM has moved, and there’s no current option for moving it elsewhere. If you don’t like that, like me, don’t use SDDM, or GDM. I prefer KDM3 or TDM, but in a pinch XDM is usable. I don’t like LightDM much better, but at least so far it still runs on tty7. And, all will run SDDM X11. Status with Wayland I can’t help with. I have yet to find a justifiable reason to use it.

Multiple display issue have been a problem with Plasma for quite some time. As of 5.26 release many bug reports have been addressed, and more in 5.27, but there are plenty left, and lots of new ones since 5.26 release.

I’ve been seeing more and more VGA trouble reported lately. I posted in another thread about this a week or less ago, with links to two Radeon bugs I reported. VGA is seriously ancient analog technology, apparently too old for more than a few, if any, graphics programmers to actually use or test with, or care about in the absence of bug reports from the few still depending on it. Digital is more reliable. If your Thinkpad only has VGA, you may be totally stuck. If it has DP, DVI or HDMI, try to use it instead of VGA. It may be the simple answer, possibly your only answer. Also if your VGA cable only has 14 pins instead of 15, try one with 15. It can make a difference.

qwert.zuiop · July 14, 2023, 10:59am

Just yesterday I shipped out 5000 DP to VGA adaters. VGA is still heavy in use.

But yes, those adapters help a lot. HDMI to DVI would be recommended.

The Syncmaster screen schould have DVI port and the E525 has a HDMI port, doesn’t it?

There are also working HDMI to VGA adapters.

dwawlyn · July 14, 2023, 12:14pm

Thanks.
Yeah, I know I was babbling, but I’d been awake over 24 hours, and just… yeah. Everything was (and still is) breaking on me.
(I got 5 or 6 hours of sleep, but just woke up again with insomnia.)

For ports out, the laptop has HDMI
[pic laptop ports out]

but my monitor doesn’t have HDMI in.

It only has VGA (labelled “RGB IN”)
and “DVI IN (HDCP)”
which from what I was able to google is actually “DVI-D (Dual link)” (“DVI-DL”)
(I honestly never even saw a DVI cable before, so this is all new to me.)
[pic monitor port labels]

[pic monitor ports]

Is there such a thing as HDMI-out–to–DVI-DL-in?
I mean, I can find physical cables with an HDMI plug on one end and a DVI-DL plug on the other,
but it’s not immediately clear if any such cable would work between this laptop and this monitor,
or if I’d need a specific variant due to some internal differences,
or what…

I mean, I guess I’ll just get one
(after checking a bit more whether I need a specific variant),
since it seems one of the few obvious solutions to try…

[EDIT:
@qwert.zuiop just saw your post too.
Is this what you meant?
Sorry, I have like zero experience with this stuff. I plugged in a VGA cable several years ago and forgot about it. So I’m kinda stupid-ignorant here…

Also, I did note (later on in this post) that lshw seems to think the HDMI port is also somehow DP…?
]

But like I said, I did confirm the monitor works fine with VGA-out–to–VGA-in under MX-Linux (their KDE version, live-usb),
so in principle you’d think there’s no reason it shouldn’t still just work under opensuse.

But I really don’t want to do any distrohopping installations right now.
With only one working computer
(with a bunch of kinda fragile custom stuff I reallly depend on, like custom keyboard layout stuff)
it just seems like a terrible idea to do anything with even a relatively small risk of rendering it unbootable…

By the way, this is probably really off-topic,
but thanks for explaining the tty stuff and display-manager stuff for me.
I personally don’t mind whether it’s on tty2 or whatever,
I was just surprised and confused to find it had changed,
and was wondering if I somehow messed up the standard config (ie in a way that was maybe affecting other stuff).

(And yeah, I accept in principle that “Wayland is the future”, but I’m still not touching it yet. Too much else to figure out first…)

But I’m really curious about why you say like:

because I’ve actually been wondering for ages:
why do people care about customizing display-managers?
Like, what concrete features/functionality does customizing your display-manager setup get you?

Cuz I looked into it a little in the past,
and all the information I could find sounded like they really just control the user login-screen to your desktop-session?
(And I just have my computers set up to login automatically at home anyway, so I practically never even see the login-screen.)

I mean, I heard the display-manager also handles the kind of stuff that xinitrc handles in non- desktop-environments
(like, with a more custom window-manager setup I mean)
but on KDE you mostly interact with that stuff through “autostart” anyway, right? (ie systemsettings kcm_autostart)
And that’s independent of the display-manager, I thought…?

Or are different display-managers somehow relevant to these kind of hardware/driver compatibility issues?
Or…?

Anyway, not sure how useful it is, but here’s the output you said I should provide:
$inxi -GSaz
#=>

System:
  Kernel: 6.4.2-1-default arch: x86_64 bits: 64 compiler: gcc v: 13.1.1
    parameters: BOOT_IMAGE=/boot/vmlinuz-6.4.2-1-default
    root=UUID=67c9ab43-05d1-41e7-97c9-8f3ef7e07255 splash=silent quiet
    security=apparmor mitigations=auto
  Desktop: KDE Plasma v: 5.27.6 tk: Qt v: 5.15.10 wm: kwin_x11 vt: 2
    dm: SDDM Distro: openSUSE Tumbleweed 20230712
Graphics:
  Device-1: AMD Sumo [Radeon HD 6480G] vendor: Lenovo driver: radeon v: kernel
    alternate: amdgpu arch: TeraScale-2 code: Evergreen process: TSMC 32-40nm
    built: 2009-15 ports: active: LVDS-1 empty: HDMI-A-1,VGA-1 bus-ID: 00:01.0
    chip-ID: 1002:9648 class-ID: 0300
  Device-2: Chicony Lenovo Integrated Camera driver: uvcvideo type: USB
    rev: 2.0 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 2-3:2 chip-ID: 04f2:b257
    class-ID: 0e02
  Display: x11 server: X.Org v: 21.1.8 with: Xwayland v: 23.1.2
    compositor: kwin_x11 driver: X: loaded: modesetting unloaded: fbdev,vesa
    dri: r600 gpu: radeon display-ID: :0 screens: 1
  Screen-1: 0 s-res: 1366x768 s-dpi: 96 s-size: 361x203mm (14.21x7.99")
    s-diag: 414mm (16.31")
  Monitor-1: LVDS-1 model: AU Optronics 0x23ec built: 2009 res: 1366x768
    hz: 60 dpi: 101 gamma: 1.2 size: 344x193mm (13.54x7.6") diag: 394mm (15.5")
    ratio: 16:9 modes: max: 1366x768 min: 640x480
  API: OpenGL v: 4.5 Mesa 23.1.3 renderer: AMD SUMO (DRM 2.50.0 /
    6.4.2-1-default LLVM 16.0.6) direct-render: Yes

(
I also tried passing it through aha to try to preserve the pretty color highlighting
(I don’t think it’s semantic here, but a way to communicate shell output without stripping away the formatting would be nice…)
but I don’t know if this forum will display it:

$pty inxi -GSaz | aha -n -b
#=>

System:
  Kernel: 6.4.2-1-default arch: x86_64 bits: 64 compiler: gcc v: 13.1.1
    parameters: BOOT_IMAGE=/boot/vmlinuz-6.4.2-1-default
    root=UUID=67c9ab43-05d1-41e7-97c9-8f3ef7e07255 splash=silent quiet
    security=apparmor mitigations=auto
  Desktop: KDE Plasma v: 5.27.6 tk: Qt v: 5.15.10 wm: kwin_x11 vt: 2
    dm: SDDM Distro: openSUSE Tumbleweed 20230712
Graphics:
  Device-1: AMD Sumo [Radeon HD 6480G] vendor: Lenovo driver: radeon v: kernel
    alternate: amdgpu arch: TeraScale-2 code: Evergreen process: TSMC 32-40nm
    built: 2009-15 ports: active: LVDS-1 empty: HDMI-A-1,VGA-1 bus-ID: 00:01.0
    chip-ID: 1002:9648 class-ID: 0300
  Device-2: Chicony Lenovo Integrated Camera driver: uvcvideo type: USB
    rev: 2.0 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 3-3:2 chip-ID: 04f2:b257
    class-ID: 0e02
  Display: x11 server: X.Org v: 21.1.8 with: Xwayland v: 23.1.2
    compositor: kwin_x11 driver: X: loaded: modesetting unloaded: fbdev,vesa
    dri: r600 gpu: radeon display-ID: :0 screens: 1
  Screen-1: 0 s-res: 1366x768 s-dpi: 96 s-size: 361x203mm (14.21x7.99")
    s-diag: 414mm (16.31")
  Monitor-1: LVDS-1 model: AU Optronics 0x23ec built: 2009 res: 1366x768
    hz: 60 dpi: 101 gamma: 1.2 size: 344x193mm (13.54x7.6") diag: 394mm (15.5")
    ratio: 16:9 modes: max: 1366x768 min: 640x480
  API: OpenGL v: 4.5 Mesa 23.1.3 renderer: AMD SUMO (DRM 2.50.0 /
    6.4.2-1-default LLVM 16.0.6) direct-render: Yes

)

Should I get the output of lshw or whatever too…?
(
I know I took a bunch of notes on different commands/flags I found recommended for getting hardware info,
but with my other computer exploded… I technically didn’t lose any information,
but my ability to actually access and search it using all the organization/tools/sessions/workspaces/muscle-memory/etc I’m used to is currently all messed up…
)

But yeah, I managed to find some notes from when I was trying to figure out some cpu and ram stuff ages ago like:

#	                        	
 	cat /proc/cpuinfo       	# cpu -- works ("model name")
 	cat /proc/meminfo       	# mem -- kinda meh
#	                        	
 	sudo lshw -c processor  	# cpu -- works ("product")
 	sudo lshw -c memory     	# mem -- works ("product")
#	                        	
 	sudo dmidecode --type 4 	# cpu -- works ("version")
 	sudo dmidecode --type 17	# mem -- works ("part number")

and I wonder if anything related to that might be helpful for troubleshooting this VGA-or-whatever problem…?

Like…

$sudo lshow -sanitize -short
#=>

H/W path             Device      Class          Description
===========================================================
                                 system         12003NG
/0                               bus            12003NG
/0/1                             memory         128KiB BIOS
/0/23                            memory         16GiB System Memory
/0/23/0                          memory         8GiB SODIMM DDR3 Synchronous 1600 MHz (0.6 ns)
/0/23/1                          memory         8GiB SODIMM DDR3 Synchronous 1600 MHz (0.6 ns)
/0/29                            processor      AMD A4-3300M APU with Radeon(tm) HD Graphics
/0/29/2a                         memory         256KiB L1 cache
/0/29/2b                         memory         2MiB L2 cache
/0/100                           bridge         Family 12h Processor Root Complex
/0/100/1             /dev/fb0    display        Sumo [Radeon HD 6480G]
/0/100/1.1           card0       multimedia     BeaverCreek HDMI Audio [Radeon HD 6500D and 6400G-6600G series]
/0/100/1.1/0         input27     input          HD-Audio Generic HDMI/DP,pcm=3
/0/100/4                         bridge         Family 12h Processor Root Port
/0/100/4/0           enp1s0      network        RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
/0/100/11            scsi0       storage        FCH SATA Controller [AHCI mode]
/0/100/11/0          /dev/sda    disk           250GB Samsung SSD 840
/0/100/11/0/1        /dev/sda1   volume         511MiB Windows FAT volume
/0/100/11/0/2        /dev/sda2   volume         99GiB EFI partition
/0/100/11/0/3        /dev/sda3   volume         39GiB EFI partition
/0/100/11/0/4        /dev/sda4   volume         7561MiB Linux swap volume
/0/100/11/0/5        /dev/sda5   volume         39GiB EFI partition
/0/100/11/0/6        /dev/sda6   volume         39GiB EFI partition
/0/100/11/1          /dev/cdrom  disk           DVD-RW DS8A8SH
/0/100/12                        bus            FCH USB OHCI Controller
/0/100/12/1          usb4        bus            OHCI PCI host controller
/0/100/12/1/3                    generic        TouchStrip Fingerprint Sensor
/0/100/12/1/5                    communication  Broadcom Bluetooth Device
/0/100/12.2                      bus            FCH USB EHCI Controller
/0/100/12.2/1        usb1        bus            EHCI Host Controller
/0/100/13                        bus            FCH USB OHCI Controller
/0/100/13/1          usb5        bus            OHCI PCI host controller
/0/100/13.2                      bus            FCH USB EHCI Controller
/0/100/13.2/1        usb2        bus            EHCI Host Controller
/0/100/13.2/1/3                  multimedia     Integrated Camera
/0/100/14                        bus            FCH SMBus Controller
/0/100/14.2          card1       multimedia     FCH Azalia Controller
/0/100/14.2/0        input28     input          HDA Digital PCBeep
/0/100/14.2/1        input29     input          HD-Audio Generic Mic
/0/100/14.2/2        input30     input          HD-Audio Generic Front Headphone
/0/100/14.3                      bridge         FCH LPC Bridge
/0/100/14.3/0                    system         PnP device PNP0c02
/0/100/14.3/1                    system         PnP device PNP0b00
/0/100/14.3/2                    system         PnP device PNP0c02
/0/100/14.3/3                    system         PnP device PNP0c01
/0/100/14.3/4                    input          PnP device PNP0303
/0/100/14.3/5                    generic        PnP device LEN0023
/0/100/14.4                      bridge         FCH PCI Bridge
/0/100/14.7          mmc0        bus            FCH SD Flash Controller
/0/100/15                        bridge         Hudson PCI to PCI bridge (PCIE port 0)
/0/100/15.1                      bridge         Hudson PCI to PCI bridge (PCIE port 1)
/0/100/15.1/0        mmc1        bus            MMC/SD Host Controller
/0/100/15.2                      bridge         Hudson PCI to PCI bridge (PCIE port 2)
/0/100/15.2/0        wlp5s0      network        RTL8188CE 802.11b/g/n WiFi Adapter
/0/100/15.3                      bridge         Hudson PCI to PCI bridge (PCIE port 3)
/0/100/16                        bus            FCH USB OHCI Controller
/0/100/16/1          usb6        bus            OHCI PCI host controller
/0/100/16.2                      bus            FCH USB EHCI Controller
/0/100/16.2/1        usb3        bus            EHCI Host Controller
/0/100/16.2/1/4                  bus            USB 2.0 Hub [MTT]
/0/100/16.2/1/4/2                input          USB Receiver
/0/100/16.2/1/4/2/0  input33     input          Logitech M325
/0/100/16.2/1/4/3                bus            USB hub
/0/100/16.2/1/4/3/1  card2       multimedia     Jabra Link 380
/0/100/16.2/1/4/7    input34     input          FalbabeTech ErgoDox ergonomic keyboard
/0/101                           bridge         Family 12h/14h Processor Function 0
/0/102                           bridge         Family 12h/14h Processor Function 1
/0/103                           bridge         Family 12h/14h Processor Function 2
/0/104                           bridge         Family 12h/14h Processor Function 3
/0/105                           bridge         Family 12h/14h Processor Function 4
/0/106                           bridge         Family 12h/14h Processor Function 6
/0/107                           bridge         Family 12h/14h Processor Function 5
/0/108                           bridge         Family 12h/14h Processor Function 7
/1                   card29      multimedia     ThinkPadEC
/2                   input0      input          AT Translated Set 2 keyboard
/3                   input21     input          TPPS/2 IBM TrackPoint
/4                   input22     input          Lid Switch
/5                   input23     input          Power Button
/6                   input24     input          Power Button
/7                   input25     input          ThinkPad Extra Buttons
/8                   input26     input          PC Speaker
/9                   input4      input          SynPS/2 Synaptics TouchPad
/a                   input5      input          Video Bus

so I guess…

$sudo lshw -sanitize -c cpu
#=>

*-cpu
     description: CPU
     product: AMD A4-3300M APU with Radeon(tm) HD Graphics
     vendor: Advanced Micro Devices [AMD]
     physical id: 29
     bus info: cpu@0
     version: 18.1.0
     slot: Socket FS1
     size: 1397MHz
     capacity: 1900MHz
     width: 64 bits
     clock: 100MHz
     capabilities: lm fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp x86-64 3dnowext 3dnow constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt cpb hw_pstate vmmcall arat npt lbrv svm_lock nrip_save pausefilter cpufreq
     configuration: cores=2 enabledcores=2 microcode=50331687 threads=2

$sudo lshw -sanitize -c display
#=>

*-display
     description: VGA compatible controller
     product: Sumo [Radeon HD 6480G]
     vendor: Advanced Micro Devices, Inc. [AMD/ATI]
     physical id: 1
     bus info: pci@0000:00:01.0
     logical name: /dev/fb0
     version: 00
     width: 32 bits
     clock: 33MHz
     capabilities: pm pciexpress msi vga_controller bus_master cap_list rom fb
     configuration: depth=32 driver=radeon latency=0 resolution=1366,768
     resources: irq:30 memory:e0000000-efffffff ioport:4000(size=256) memory:f0b00000-f0b3ffff memory:c0000-dffff

(
Also, I think the HDMI out from the laptop is maybe also DP?
Because:
$sudo lshw -sanitize|ag '\b(hdmi|dp)'
#=>

product: BeaverCreek HDMI Audio [Radeon HD 6500D and 6400G-6600G series]
   product: HD-Audio Generic HDMI/DP,pcm=3

(It only mentions audio there, but I think the video matches?)

Is that a thing? An HDMI-out physical port that can go directly to DP-in on the other end?

(Again, I have like zero experience with this stuff. I plugged in a VGA cable several years ago and forgot about it.
)

dwawlyn · July 14, 2023, 12:23pm

Hi, thanks, I just saw your post after posting a long reply,
so I edited in an @ to you in the section of my long post that was relevant to what you said
(I’m not super sure I’m using all the forum features here right, but yeah.)

EDIT:
Case in point, just accidentally sent that early
(hit ctrl-enter cuz muscle-memory-interference from… I’m not even sure what)

I was gonna add:
should something like this be compatible?:

qwert.zuiop · July 14, 2023, 12:42pm

DVI= HDMI -audio

The difference between DVI and HDMI is the missing audio transfer. There is no conversion, but only a stupid adapter that changes the pins.

dwawlyn · July 14, 2023, 12:59pm

Oh! So it’s way simpler than I thought it was gonna be!

I guess I was kinda afraid it was gonna be like the situation with USB-C,
where you have a bunch of cables that look identical,
but all these internal complications as to whether they support power and data, or just power, or just data, or to what specific spec,
so you’re always having problems as to what cable actually works with what device…

But for HDMI-out–to–DVI-in, if the cable is physically correct, it’ll just work?

dwawlyn · July 14, 2023, 1:24pm

Oh and btw, that thing about HDMI including audio-out…

Is the HDMI-audio-out combined with the DP-audio-out?
Or at least, are they commonly combined together?

like, the bit I spotted in the output of:
$ sudo lshw -sanitize|ag '\b(hdmi|dp)'
#=>

product: BeaverCreek HDMI Audio [Radeon HD 6500D and 6400G-6600G series]
   product: HD-Audio Generic HDMI/DP,pcm=3

that does mean that I could in theory stick a cable with an HDMI-out plug into that port,
and get DP audio-out the other end somehow?

(Mostly just asking out of pure curiosity here, figuring it’s just a good idea to try to become generally less ignorant…)

qwert.zuiop · July 14, 2023, 2:00pm

HDMI and DVI are basically the same thing difference is audio.

DP and HDMI both Transport audio.
HDCP Transports Copyright Potection/ encryption.

HDMI vs DisplayPort — Which One Should You Use? |.

Yes, there is stupid adapter HDMI female to DVI male available, that you can use together with a standard HDMI cable.

DVI / HDMI / DP are all digital output for what simple adapters are available
HDMI DVI passiv
DP to DVI/HDMI/VGA requires active adapters.

dwawlyn · July 14, 2023, 2:25pm

Thanks!

I actually noticed that while I was googling it.
The fact my monitor’s DVI-DL-in has that HDCP crap won’t affect me in any way though, right?

Like this thing?

https://www.amazon.ca/Benfei-Bidirectional-Female-Adapter-Gold-Plated/dp/B07CXY79KR/ref=sr_1_10?keywords=hdmi+dvi-dl&qid=1689339042&sr=8-10

I actually did just find a cable in my box of random old junk,
with one end male HDMI and the other male DP.

So then, going from what you said, I’d guess that’s:

either a passive HDMI to DP unidirectionally
or else an active HDMI/DP either direction

right?

mrmazda · July 14, 2023, 3:09pm

Technical quality of VGA when compared to digital is usually readily apparent to people with average visual acuity. And unlike VGA where it is common, digital usually won’t need the display re-adjusted for horizontal or vertical centering if switching PCs or gfxcards lacking digital outputs.

IME, DVI-HDMI always works reliably in both directions whether cable or adapter, as long as the cable/adapter aren’t damaged or junk. It’s seriously common for physical DVI connections on gfxcards and motherboards to be labeled HDMI by the operating system. DVI actually can carry audio, but usually you’ll find it’s not supported by the hardware configuration of either sending end and/or receiving end regardless of cable or adapter type used.

Both my DP-HDMI adapters are useless for converting HDMI output to DP input. Sometimes they’re useless for converting DP output to HDMI input, but all such converters are supposed to work in that direction.

When shopping for motherboards and gfxcards, my first choice is DP, meaning if I can’t have both, I choose DP only, because it’s reliable converted to HDMI input, and because DP connectors cannot be accidentally disconnected.

IME, some early gfxcards with DPs, older than your BeaverCreek/Terascale 2, shipped without any audio support.

I have my browser that I use for forums specially configured to only show black text on white background for main and PRE text regardless of any colorization supplied. Via /etc/inxi.conf, I have inxi colorization disabled, so no opportunity to be annoyed by color combinations hard on my old eyes.

dwawlyn · July 14, 2023, 6:23pm

Interesting, thanks!

Well, I’ll get my adapter/cable soon and hopefully that works.

I guess I still really should report the bug on principle though, eh…
Unecessary regressions of functionality like that are just… they make penguin sad.
And maybe there’ll be someone later with only a VGA cable in even more of disaster/emergency than I was…
I guess I should ask on the KDE forums?
(Ugh, just so much else to do…)

(
Yeah, I agree on the color not being needed here,
I just figured the forum should have a way to communicate it,
since it’s sometimes relevant to the issue you’re dealing with.
(Well, I made a note to mention it to the “Discuss.org” people, but who knows when I’ll actually get around to that…)

btw, black-text-on-white is better visibility for you than the opposite bright-text-on-dark-background?
Because I’ve been curious for a while about why dark-text-on-bright background is the popular default,
since I personally find I have significantly more visibility problems with the dark-on-bright,
with bright backgrounds tending to cause me tension headaches.
)

Oh yeah, and did you mean that switching/customizing display-managers might be somehow useful…?

dwawlyn:

But I’m really curious about why you say like:

mrmazda:

I prefer KDM3 or TDM, but in a pinch XDM is usable.

because I’ve actually been wondering for ages:
why do people care about customizing display-managers?
Like, what concrete features/functionality does customizing your display-manager setup get you?

Cuz I looked into it a little in the past,
and all the information I could find sounded like they really just control the user login-screen to your desktop-session?
(And I just have my computers set up to login automatically at home anyway, so I practically never even see the login-screen.)

I mean, I heard the display-manager also handles the kind of stuff that xinitrc handles in non- desktop-environments
(like, with a more custom window-manager setup I mean)
but on KDE you mostly interact with that stuff through “autostart” anyway, right? (ie systemsettings kcm_autostart)
And that’s independent of the display-manager, I thought…?

Or are different display-managers somehow relevant to these kind of hardware/driver compatibility issues?
Or…?

mrmazda · July 14, 2023, 10:47pm

Why does anyone like what the like, or not what they don’t? Gnu/Linux is generally about having choices, multiple ways to get to the same end, or different ends.

Most recent iteration of kdmrc/tdmrc is 22k, a result of many years of developing what people could and/or did want maturing. Compare that to SDDM or LightDM and you’ll see they provide limited functionality and customizability in comparison. The default non-themed built-in “theme” in kdmrc/tdmrc is compact, locating all functionality in a handy screen segment that can be located anywhere on the display, instead of typical other themes that try to sprawl itty bitty bits over the whole screenspace, which makes tabbing an exercise in frustration, and requires massive mouse movements for context changes. Neither SDDM nor LightDM offer the option to list specific users. Users can be omitted by userid:groupid range, but not simply listed by username.

FWIW, someone in Fedora apparently continues to recognize the value of the years of effort that went into KDM. Many years after most/all? other distros, and upstream, dropped it from their default repos, and most from their optional repos too (openSUSE being the sole optional repo keeper I’m aware of), KDM keeps on ticking in Fedora via default repos, by default on tty7.

deano_ferrari · July 15, 2023, 2:37am

[quote=“mrmazda, post:2, topic:167597”]
Upstream recently hijacked tty2 for Plasma to run on, and IIRC, that’s also where SDDM has moved, and there’s no current option for moving it elsewhere. If you don’t like that, like me, don’t use SDDM, or GDM. I prefer KDM3 or TDM, but in a pinch XDM is usable. I don’t like LightDM much better, but at least so far it still runs on tty7. [/quote]

I am not sure why the obsession with which tty the display manager starts on, but with SDDM at least, it can be configured…
https://wiki.archlinux.org/title/SDDM#SDDM_starts_on_tty1_instead_of_tty7

dwawlyn · July 15, 2023, 3:16am

I don’t really care either,
but I guess people are often trying to access the ttys when something is going wrong in the graphical session,
which means stuff is probably generally lagging/freezing or otherwise acting weirdly,
so if you go to hit the key combo you think should escape from the graphical session to a tty,
and it does nothing,
that can be pretty confusing if you end up thinking the reason it’s doing nothing is because your system is SUPER laggy/broken,
but really you just hit the combo for the tty you were already on in the graphical session.

Like, I got used to tty7 being the xsession,
so I got in the habit of escaping to tty1 by default.

Then I started finding distros that put the xsession on tty1,
so I got in the habit of escaping to tty2 by default.

And now that I’ve run into a distro that’s using tty2,
I guess I’ll start trying to escape to tty3 by default now.

But yeah, other than that, I have no clue if there’s some other reason anyone really cares?

I mean, I guess if you run into an otherwise minor annoyance (like “that didn’t immediately take me to a tty like I expected”)
in the context of dealing with a major problem (like “my xsession is freezing/lagging/etc”)
then the minor annoyance gets a lot of extra negative emotion attached due to the major problem you were already dealing with?
So maybe it’s just that?

mrmazda · July 15, 2023, 5:02am

The latest release of SDDM seems to have made that page section obsolete at least for TW users:

Trying to connect external VGA monitor freezes and breaks everything (needs reboot). Confirmed works on same computer with another distro (MX-Linux). *Maybe* radeon driver problems? KDE plasma Xsession. Old "Thinkpad E525" laptop

Trying to connect external VGA monitor freezes and breaks everything (needs reboot). Confirmed works on same computer with another distro (MX-Linux). Maybe radeon driver problems? KDE plasma Xsession. Old "Thinkpad E525" laptop