I tried to install plasma 5.5.1 on a very old PC ( pentium 2.4 Ghz, graphic card radeon 9000 AGP ) with archlinux 32 bits, the driver for the graphic card : radeon open source driver, and I get only a black screen at startup, the PC seems frozen, I tried with startx : black screen and no cursor mouse, the PC is frozen, sddm seems to have the same problem : a black screen, I am unable to see the login/password page, what are the minimal hardware requirements in order to use plasma 5 ? it seems that plasma 5 can not boot if the graphic card supports only openGL 1.3, there is someting in plasma 5 who prevents old graphic cards to work, if I use kdm and kde 4.x there is no problem with this old PC, and there is also no problem with lxqt ( who uses Qt5 libs ) Reproducible: Always Steps to Reproduce: 1. install plasma 5.5.1 on a very old PC ( from 2003 for example, with a graphic card who supports only openGL 1.3 ) 2. try to boot plasma 5.5.1 ( startx or sddm ) 3. you will get a black screen at startup, with keyboard frozen and no mouse cursor Actual Results: black screen, keyboard frozen and no cursor mouse Expected Results: plasma 5.5.1 should start on old PCs, even if the graphic card is very old and supports only openGl 1.3
This is known: KDE Plasma 5 needs OpenGL 2. Try use Software accelerator instead of hardware: echo 'QT_XCB_FORCE_SOFTWARE_OPENGL=1' > ~/.bashrc echo 'LIBGL_ALWAYS_SOFTWARE="true"' > ~/.bashrc This will add two line in /home/[username]/.bashrc : QT_XCB_FORCE_SOFTWARE_OPENGL=1 LIBGL_ALWAYS_SOFTWARE="true" Or you can create /etc/xdg/plasma-workspace/env/plasma-Qt5-OpenGL2.sh file with content (and make this file executable): #!/bin/sh OPENGL_VERSION=`LANG=C glxinfo | grep '^OpenGL version string: ' | head -n 1 | sed -e 's/^OpenGL version string: \([0-9]\).*$/\1/g'` if [ "$OPENGL_VERSION" -lt 2 ]; then QT_XCB_FORCE_SOFTWARE_OPENGL=1 export QT_XCB_FORCE_SOFTWARE_OPENGL fi
Comment 1 is correct. If the suggested env var does fix your issue, please file a bug with Qt.