Hi All,

I've recently bought a new laptop that came with 4K display. I also have old 1680x1050 external Samsung monitor.

I though of using Windows 10 on the machine and Windows 10 does give an option to use different scaling on different monitors. But, I've been using Linux with KDE for quite a few years now, and most things about Windows annoy me now. So I want to switch back to Linux (OpenSUSE Tumbleweed to be precise). I do face an issue though. I've got Plasma 5.5.4 installed and through changing DPI and icon sizes I somewhat have screen scaling to a usable state (not perfect) on my laptop screen. Unfortunately, those DPI and icon size settings seem to be global and everything on my external monitor is roughly 30% too large. Is there a way to fix this screen scaling issue in dual screen set-up?

see viewtopic.php?f=66&t=130848&p=353441&hilit=hidpi#p353441

google01103 wrote:see viewtopic.php?f=66&t=130848&p=353441&hilit=hidpi#p353441

Thank you, that is interesting. I hope it works the way it is described. I've tried installing it from the OpenSUSE repos, but I can't get GUI at all now
I guess I have some experimentation ahead.

might be your graphics drivers as I'm running QT 5.6.0 & Plasma 5.6.2 fine but have no HiDPI monitors

google01103 wrote:might be your graphics drivers as I'm running QT 5.6.0 & Plasma 5.6.2 fine but have no HiDPI monitors

Hmm. Maybe. I didnt install anny drivers so I was running default intel and nouveau on nvidia primus laptop with default settings.

Hmmm, was thinking that if you self compiled the drivers

can you boot into safe mode iirc at boot, at grub menu select advanced then safe mode

google01103 wrote:Hmmm, was thinking that if you self compiled the drivers

can you boot into safe mode iirc at boot, at grub menu select advanced then safe mode

I'm afraid i haven't got a save mode option in grub.

Either way, thank you for the tip on Qt 5.6.
This system was my test set-up with no valuable data on it. It will be quicker if i try installing Qt 5.6 on a fresh install.

Btw, what repo did you install Qt 5.6 from?

Tumblweed should have have latest QT 5.6, see https://en.opensuse.org/SDB:KDE_reposit ... 5_releases

Releases of KDE Frameworks 5 and Plasma 5. Since openSUSE 13.2, KDE Frameworks 5(KF5) libraries, and Plasma 5 components are part of the standard distribution repositories. If you want test and/or use the latest release, you can use this repo. Factory/Tumbleweed users do not need (but can, if they want) to use it, as new releases are submitted to Tumbleweed as soon as they're available, and are usually published to standard repositories in a matter of days.

google01103 wrote:Tumblweed should have have latest QT 5.6, see https://en.opensuse.org/SDB:KDE_reposit ... 5_releases

Releases of KDE Frameworks 5 and Plasma 5. Since openSUSE 13.2, KDE Frameworks 5(KF5) libraries, and Plasma 5 components are part of the standard distribution repositories. If you want test and/or use the latest release, you can use this repo. Factory/Tumbleweed users do not need (but can, if they want) to use it, as new releases are submitted to Tumbleweed as soon as they're available, and are usually published to standard repositories in a matter of days.

Hi there. So I tried to boot 2 day old Tumbleweed and it would boot. So I tried Leap. Added KDE:QT5 repo and... it turns out that half of plasma is not compatible with Qt 5.6.

Are you using OpenSUSE or some other distro. Since you have plasma5 and Qt 5.6 playing together nicely, I'd like to know the repos you used, so that I can give them a try as well.

http://download.opensuse.org/repositori ... Leap_42.1/
http://download.opensuse.org/repositori ... Leap_42.1/
http://download.opensuse.org/repositori ... Leap_42.1/
http://download.opensuse.org/update/leap/42.1/non-oss/
http://download.opensuse.org/distributi ... /repo/oss/
http://download.opensuse.org/update/leap/42.1/oss/
http://download.opensuse.org/repositori ... Leap_42.1/
http://download.opensuse.org/repositori ... _Leap_42.1
http://download.opensuse.org/update/leap/42.1/non-oss/

Thank you, your list of repos helped me to install Qt5.6. So now I have
KDE Plasma 5.6.3
KDE Framework 5.21.0
Qt 5.6.0
nouveau is disabled both by entry in blackilst.conf file and in grub parameters.

on 64bir OpensSUSE 45.1 with kernel 4.1.12.-1-default
Kernel 4.1.20 does not boot. There are a bunch of other issue, but I'll leave those to OpenSUSE forums.

So, how is this HiDPI scalling suppose to work? Do I need to enable it somewhere? Because I see no difference.

no HiDPI so no way to test

see https://wiki.archlinux.org/index.php/HiDPI, appears KDE, Gnome, QT, FireFox, etc .... needs to be individually set

google01103 wrote:no HiDPI so no way to test

see https://wiki.archlinux.org/index.php/HiDPI, appears KDE, Gnome, QT, FireFox, etc .... needs to be individually set

Hi, thank you for the link, but it is of no help I'm afraid. Setting higher font DPI worked in earlier Plasma/Qt the same way. And my issue remains the. i.e. if I set larger DPI font - I get properly sized UI elements and fonts on my laptop screen, but everything is way too large on my external monitor.

Seems that magic HiDPI switching announced in Qt 5.6 beta didn't make into the release.

maybe this is what you need to use http://blog.davidedmundson.co.uk/blog/high_dpi_again

google01103 wrote:maybe this is what you need to use http://blog.davidedmundson.co.uk/blog/high_dpi_again

Thank you, but I'm afraid this one has the same flaw - namely, it is a global setting. So If UI looks right on my HiDPI laptop screen, it is too large on external. And if it looks right on external monitor, UI is way too small on HiDPI laptop screen.