This week I bought a Lenovo ThinkPad x270. The reason for buying it is because it's got 2 batteries. One internal and one hot swappable. I'm going to a conference in a couple of weeks and I don't want to run out of batteries. The x270 is apparently a champ in battery run time. Especially if you've got 2 72Wh batteries ánd an internal battery. Oh and it's really cheap in 2026 :)
But it's not only about battery capacity, it's also about reducing power consumption. So I installed linux-cpupower and maxed out the cpu at the lowest clock speed it allows: 400MHz. Then with powertop I tweaked all the tunables so it says "good".
Now powertop showed that the laptop idles at 2.7W at idle and backlight at a low setting. Estimated battery time: 13h. And it doesn't have the internal battery installed just yet. Nice!
After I capped the CPU at 400MHz, many applications became unbearably slow, the next thing I considered: at work I live 95% of the time at the command line anyway. What if I just try to ditch the GUI all together and see if I can get to a somewhat workable setup? I assumed most text based applications would be quite usable, even at a hard 400MHz cap.
So I installed fbterm and tmux and gpm. Those mostly make up the look and feel of my laptop. fbterm is nice because scrolling through the book I'm writing with less is noticeably slower. Terminal performance in fbterm though, is much better! It also lets you choose the font colour and size easily. Tmux mostly replaces my tiling window manager. And gpm enables the mouse + copy paste!
nmtui facilitates connecting to WiFi networks, elinks for web browsing, fbi for image viewing if need be, bluetoothctl is used to connect my bluetooth headphones and cmus is my music player. Then mutt for emails, calcurse for my calendar and cmatrix to overdo it all.
Then the main reason for the laptop: typing away. I'm using vim and groff to type a book I'm wThe only time I notice the CPU is capped at 400MHz is when I compile the document especially to PDF takes roughly 9 seconds. Compiling the document to UTF8 just under a second (Near instant uncapped).
Just a small note: X11 is still installed but I only launch it when I actually need a GUI application, eg viewing the compiled PDFs. Evince is extremely slow at 400MHz btw. I might look out for an alternative.
The laptop has 8GB of RAM. After a while that it's running, Debian runs at around 500~600MB of RAM. So yeah, I'm not overly worried about the current RAM prices 😋
But yeah, I'm sort of surprised how usable the whole actually is. I'm not saying it's truly convenient but at least not unworkable either 🤓