Lenovo’s T450s is another piece of high-production-volume hardware from a vendor with a fairly good reputation for Linux support … but a host of serious problems under Ubuntu’s flagship “Long-term-support” operating system. I’d love to be in touch with others running this machine, to know whether these are all common symptoms for you:
Hardware-ish Problems as of June 2016:
- This has varied in its details with updates since I first installed, but currently my laptop cannot shut down at all. When I shut it down with software, it just hangs on the moving-dots screen. https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1573597
- Undocking the laptop from Lenovo’s superdock (to which I have a Wacom tablet attached) makes unity-settings-daemon crash, which leads to various secondary failures until I’ve rebooted twice. Not infrequently, the machine locks up. https://bugs.launchpad.net/ubuntu/+source/unity-settings-daemon/+bug/1439427 [Update: fix released to xenial-proposed]
- After booting, RAM use steadily climbs to fill nearly all of the 20GB I have, even though nothing is using it https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1585598
- Fingerprint scanner keeps flashing after use, requiring second/useless scan https://bugs.launchpad.net/ubuntu/+source/fprintd/+bug/1588815
- Disabling of the touchpad while typing, a standard feature to avoid the mouse pointer jumping around randomly, does not work. This old(!) bug report contains a work-around; the -t option of syndaemon is not working, so should not be used: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1581491
Beyond that, there are various software problems with Ubuntu 16.04. I have filed bugs about apt-mark hold, banshee, biber [update: fix released], etc. But these are not particular to my hardware.
Also, for some bizarre reason, although I more or less maxed out the specs on this machine, the keyboard backlight does not work, which apparently means I bought one without! Careful not to do that.
The Red Pen 
I have updated to the Kernel 4 and it improved some of the feature of the Lenovo ( I am on Linux mint) Still find very annoying that the intel and nvidia switch is too complicated to setup.
Glad to hear it.
I’m already using kernel version 4.4.0-24-generic, which is the default for Ubuntu 16.04. Is that what you mean by Kernel 4?
I was asked to try the “mainline kernel” for one bug report. I tried to follow the directions, which don’t seem to be aimed at people like me, and couldn’t get them to work.