While ThinkPads are known for wonderful Linux support, it may still happen that things are not working perfectly by default. But hey, there are workarounds available as every so often... and they often are compatible with other computers as well.

Table of contents:
TouchPad / ScreenTearing / Bad Render Performance / PulseAudio DP/HDMI Fix

TouchPad

The T440 is known for it's wonderf.. oh wait, anyway, you may encounter an issue where two-finger-scroll suddenly stops working - as far as I remember, this usually happens when it wakes up from suspend.
The fix/workaround for that is to add a kernel parameter called psmouse.synaptics_intertouch=0. It belongs to /etc/default/grub (in case ur using GRUB). The upper part of this config then gonna look something like this:

GRUB_DEFAULT=0
GRUB_TIMEOUT=2
GRUB_DISTRIBUTOR="Arch"
GRUB_CMDLINE_LINUX_DEFAULT="psmouse.synaptics_intertouch=0"

After you're done editing, run the command grub-mkconfig -o /boot/grub/grub.cfg in order to apply the new changes.

Graphics

Render Issues for moving 2D objects / video (Screen Tearing)

In case you're using Xorg instead of Wayland, you may encaunter screen tearing (yes, I use Wayland and didn't run into this problem, but I did when setting up Solus on a T450 with Xorg, actually). So if you have this issue, the following config may be interesting for you:

# /etc/X11/xorg.conf.d/20-intel.conf
Section "Device"
  Identifier	"Intel Graphics"
  Driver	"intel" # adjust it according to your setup otherwise you'll get a "no screens found" error
  Option	"TearFree" "true"
EndSection

After doing that, a simple re-login into your desktop environment should be enough to apply this change. However, this may have some disadvantages as to read in the ArchLinux Wiki, so if you have the option, consider trying Wayland first.

Low FPS, stuttering, slow rendering mainly to notice in 2D

As to read in the ArchWiki, this issue is often coming along with upon workaround, however it affects me too, even without using this. This issue is esp. annoying because the T440's screen already comes with a poor refreshrate and effects of the desktop environment or loading animations in the browser, ... (the list is long).

However luckily there is a very simple workaround: Disabling a powersaving feature called Panel Self Refresh (PSR).

For this, add the kernel parameter i915.enable_psr=0 to your bootloader config, so in case of GRUB and with the ClickPad fix from above, the upper part of your /etc/default/grub config would look like this:

GRUB_DEFAULT=0
GRUB_TIMEOUT=2
GRUB_DISTRIBUTOR="Arch"
GRUB_CMDLINE_LINUX_DEFAULT="psmouse.synaptics_intertouch=0 i915.enable_psr=0"

After you're done editing, run the command grub-mkconfig -o /boot/grub/grub.cfg in order to apply the new changes. I've personally noticed that this issue comes back for some moments after the screen wakes up, but after that it seems to be fine.. .

No HDMI/DisplayPort Sound

I recently attempted to make it more quiet on my desk, by using the ThinkPad for stuff that I don't need my desktop for. So I got me a HDMI<->mDP cable and used my desktop's screen as a kinda audiobridge as it already extends the ThinkPad's display (or reverse) ... so there is one less cable.

However it was indeed quiet - as there was no sound at all. After some research in the holy ArchLinux Wiki, I found an entry in the Troubleshooting page for PulseAudio.

It advised to comment the following inside /etc/pulse/default.pa:

### Should be after module-*-restore but before module-*-detect
#load-module module-switch-on-port-available

It was perfectly fine than - except very terrifying noises on screen-wakeup/suspend, hm. But it works!


Alright, i hope this helped some of you, here are some reference links:

Have a nice day.