Life with modern Thinkpad T14 Gen 5

Due to the deteorating situation with my old Lenovo Ideapad 5 14are05 with ryzen 4500U I have been forced to upgrade my machine. It was no longer bearable to use it. The keyboard was getting very bad, whole column with keys F10, 9 o l . was stopping function which was hinting either keyboard or motherboard issue. In addition it seemed like only the right one USB-A port was functioning, I was getting ton of errors from the USB-C and far right USB-A in the kernel log. This has been further tested with windows 10 when connecting my USB-C dock bluescreened the laptop immediately. With these issued I think the MB is in poor condition and replacing that component is not cheap nor economically valid.

So I have upgraded to Lenovo ThinkPad T14 Gen5 AMD with Ryzen 7 PRO 8840U, 64 GB RAM and 4 TB NVMe SSD. Specs wise this is a big upgrade. The build feels fine too, keyboard feels even better than the consumer grade ideapad lineup of Lenovo laptops. I have had no problems with the switch. But unfortunately this new machine is not as perfect as I thought. Notable the battery life / battery performance.

Since I have been using NixOS on my workstation when I got this laptop, I have choosed to go with NixOS on this laptop as well. So far the experience is fine. But this short article is not supposed to be about NixOS itself, about that maybe later.

The biggest dissapoitment I have had with this model is it’s 52.5 Wh battery and the laptop efficiency. Coming from Idapad 14are05 I have expect the same or better battery life. I could do ~7W low performance work without problem. On this laptop that is more like 10-13W when doing basic things. This consumed energy can be really felt when using it on my lap in train as it warms you pretty well.

I have tried different power settings, governors, tools to optimize the CPU load, but nothing was significant. Unfortunate. I have spoken with collegues who had the same model and they report the same issue that the battery life is terrible. Oh well…

I have experinced problems with the fingerprint reader stopping to work when locking and going into sleep. Even after trying tips I have found on ArchLinux wiki I was not able to get it working, but at least it was a bit better. The first change into the right direction was setting different PAM ordering for the KDE login screen:

security.pam.services.login.rules.auth.fprintd.order =
                      config.security.pam.services.login.rules.auth.unix.order + 10;
security.pam.services.kde.rules.auth.fprintd.order =
                      config.security.pam.services.kde.rules.auth.unix.order + 10;
security.pam.services.sudo.rules.auth.fprintd.order =
                      config.security.pam.services.sudo.rules.auth.unix.order + 10;

The redeption came with the NixOS 25.11 update when it magically started to work! No freeze after the update:

Linux klimipad 6.12.63 #1-NixOS SMP PREEMPT_DYNAMIC Thu Dec 18 12:55:23 UTC 2025 x86_64 GNU/Linux

I have also tried using the latest kernel but this was once again not working and I got a freeze pretty soon:

Linux klimipad 6.18.1 #1-NixOS SMP PREEMPT_DYNAMIC Fri Dec 12 17:42:47 UTC 2025 x86_64 GNU/Linux

So at least I have my working version and I know that it is not a hardware fault. Hopefully in the newer version of NixOS they won’t break it.

Sometimes when I am plugged into a charger (not the original 65W just a a multi USB PD one) my touchpad gets quite laggy and I have not found the reason why it does such things. Using usb mouse or the trackpoint is not affected. CPU governor, CPU frequency, I/O seems all okay. It is not very distruptive as it is just a small delay/latency and it does not happend frequently. It might have do something with getting lower than 65W USB-C power, but I have not been able to find the exact cause.

The laptop has very quiet fan, when idling it is spun down and you can only hear the powersupply’s (or some other components) electrical whinning noise. This is nice when you want your laptop to be quiet, but what when you want the full performance, because you need to compile ton of packages like gcc or llvm? When updating firmware you can hear the fans spin up to max, so why can’t we utilize such cooling? Well we can if we utilize thinkfan package.

NixOS has even a service for it! You probably don’t need most of the settings except the enable and levels. Without levels it switches to level automatic on full load which doesn’t seem to spin up the fans at all. So this is why i have set up the level full-speed from 70°C and up. When i don’t need this extra cooling i can just stop the service with sudo systemctl stop thinkfan and it seems to go back to the firmware management.

services.thinkfan = {
  enable = true;

  # ThinkPad ACPI sensors
  sensors = [
    {
      type = "tpacpi";
      query = "/proc/acpi/ibm/thermal";
    }
  ];

  # ThinkPad fan control
  fans = [
    {
      type = "tpacpi";
      query = "/proc/acpi/ibm/fan";
    }
  ];

  # Fan curve
  levels = [
    # [ LEVEL   LOW   HIGH ]
    [ 0        0     45   ]
    [ 1        40    50   ]
    [ 2        45    55   ]
    [ 3        50    60   ]
    [ 4        55    62   ]
    [ 5        60    65   ]
    [ 6        64    67   ]
    [ 7        65    72   ]
    [ "level full-speed" 70 32767 ]
  ];
};

In my past experience with full disk encryption the method using DM with LUKS is not optimal and I have seen a big performance hit. This performance hit was so severe it made my system freeze as long there was a little I/O. Monitoring the state with iostat (from the sysstat suite) I have seen so little writes as 4 MB/s and write latency big as 1 minute. This is not good. It is probably due to my mismanagement of the system, although I am not aware of what the mistake could be. If you have ideas, feel free to write me an email :-)

Well but what if my laptop has some confidential material and I do not want to simply leave it unencrypted for whoever find my laptop? (hopefully that never happens, but…) Well that’s when i got a tip that the modern NVMe drives are encrypting the memory anyway, so why not use the self encrypting to our advantage? On this laptop from my short testing it works flawless. Encryption is set in UEFI/BIOS and it has available 2 modes single and user+admin. If you are the solely owner of laptop then use only single password for unlocking and management. If in enterprise maybe the dual password scheme might be better for you. The password is prompted with each power-on of the system from UEFI (the whole process is managed by UEFI).

I am not sure how this scheme is secure, if the password for the NVMe controller travels on the bus in plain format or that is implemented. In my mind it does not much matter - the attacker would have to have physical access to the device when i would be unlocking the device. Which could be broken by having the keyboard snoop on my keypresses anyway.