Find a way to workaround. I have a PowerEdge R620 which installed a Ubuntu 12.04 TLS. And I found the screen refreshing became very slow. So I share the same issue with yours.
First,then we have to install vesa driver: sudo apt-get install xserver-xorg-video-vesa Then, for some of the Ubuntu release don't have a xorg.conf, so I have to generate one with following steps: 1.switch to console mode: Alt+Ctrl+F1 2.kill x server: sudo service lightdm stop 3.generate new xorg.conf file: sudo X -configure -- this will create xorg.conf.new file in your current dir 4.rename and move: sudo mv xorg.conf.new /etc/X11/xorg.conf 5.open /etc/X11/xorg.conf, replace the graphic driver of 'mga' with 'vesa'.t 6.return to GUI: sudo start lightdm ** Attachment added: "Capture.PNG" https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1316035/+attachment/4317967/+files/Capture.PNG -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1316035 Title: matrox g200eR2 is unclaimed in 14.04 Status in xorg-server package in Ubuntu: Confirmed Bug description: On a certified Dell PowerEdge T620 server (http://www.ubuntu.com/certification/hardware/201207-11426/) The matrox video card is not recognised: lspci | grep VGA 0a:00.0 VGA compatible controller: Matrox Electronics Systems Ltd. G200eR2 lshw -C display *-display UNCLAIMED description: VGA compatible controller product: G200eR2 vendor: Matrox Electronics Systems Ltd. physical id: 0 bus info: pci@0000:0a:00.0 version: 00 width: 32 bits clock: 33MHz capabilities: pm vga_controller bus_master cap_list configuration: latency=64 maxlatency=32 mingnt=16 resources: memory:d8000000-d8ffffff memory:deffc000-deffffff memory:de000000-de7fffff Thus xserver is not hardver accelerated. Also /dev/dri and /dev/dri/card0 is missing. kernel module mga is not loaded, although if i manually load by modprobe it works fine modprobe mga lsmod | grep mga mga 40811 0 drm 302817 1 mga To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1316035/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp