On Saturday, 30 April 2016 13:44:54 BST Terry Coles wrote: > > > I think I've also seen this on my Dell XPS 13 laptop running Ubuntu > > > 16.04, so the problem may not be KDE related. > > > > Have they both got similar graphics hardware? > > No. This machine has an NVidia GT 720 and the XPS has an Intel Iris > Graphics 540.
An update on this which I tracked down this morning. Apparently this issue *is* apparent on both Kubuntu and Ubuntu and, depending on your hardware, can be caused by two distinct problems: Skylake Processors with Iris graphics chipsets: Apparently someone at Intel or Canonical 'forgot' to include support for these processors, so although the machines appear to work, freezing mouse pointers and complete unresponsive machine are being extensively reported. The latest kernel (4.4.48) is supposed to fix this along with issues on AMD graphics cards and a bunch of other stuff. See http://linuxdaddy.com/blog/install-kernel-4-4-on-ubuntu/ Proprietary Driver Support on Kubuntu: Very similar symptoms seem to be occurring on Kubuntu and one of the first things anyone does is to check the graphics drivers. Unfortunately, there's a bug in the Driver Manager which never returns from the 'checking your system' process, see https://bugs.launchpad.net/ubuntu/+source/kubuntu-driver-manager/ +bug/1530523. Consequently, out-of-the-box, Intel machines have no microcode support and if you have a graphics card that would benefit from a proprietary driver it isn't there to install. These drivers can be installed from the repository, but you have to know which ones you want (I got it wrong and killed X functionality until I had installed the right nVidia driver). So far, both machines seem to be pretty stable, but the problem is intermittent, so I may be simply indulging in wishful thinking. I have to say that, yet again, Canonical seem to have released a version too early; pretty unforgivable for an LTS version. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2016-06-07 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
