Until recently, my daily driver was the T500 (the larger screen version of the T400 in the article), and it worked fine for everything except GPU.
(I actually downgraded to the T500 years ago, because I was pissed off about the Intel Management Engine.)
Recently, I upgraded from the T500 to the T520, which is the last ThinkPad with a non-chiclet keyboard. It works fine for everything except GPU and fitting inside many backpacks.
With ThinkPads of this era, you want to get a high-spec variant of the model (e.g., top-res IPS display), and then make the following upgrades:
* SSD
* run Linux
* run uBlock Origin (and block most of the surveillance trackers that kill performance) (JS runs fine, so long as you're not running multiple dueling adtech slimeballs' intimate mouse trackers)
* max out the RAM (you don't need that much for Linux unless, you're using an exceptionally bloated desktop option, but it's cheap, and you can use it to keep filesystems like ~/.cache off your SSD )
* (optional) replace the CPU with a more optimal one for power draw or heat, or maybe for compute (these are socketed in most models)
* (optional, not for the faint of heart) install Coreboot, and then you have more WiFi upgrade options
I have a T430 with the T420's keyboard and it lasted me 7 years of daily use before battery life became too big of an issue for me (even with a single DDR3L RAM module and a slice battery), so I put it aside. The typing experience was really excellent.
Upgrading the CPU to a quad-core model (ideally one that consumes 35W over 45W) is one of the best upgrades to make for anyone still using these machines.
(Last time I looked, it had the air of the XDA-style culture: "To root your phone, download this package from a `.ru` piracy site, run the `.exe` on your PC, then install and run the closed blobs on your phone, including rooting and replacing your bootloader with one, we know you will trust us." Though, in their defense, if they were organized crime, they would probably make an effort to look more legitimate, rather than gratuitously suspicious. And all the forum comments were always lapping it up, appearing to be doing reckless things, while removing much of the demand and contributors for more-credible efforts.)
You can manually recreate the process of building a patch for the embedded controller instead of just following instructions: https://github.com/hamishcoleman/thinkpad-ec. Here's the presentation by the author himself at linux.conf.au (what used to be the biggest local Linux conference for those of us in Australia and NZ): https://www.youtube.com/watch?v=Fzmm87oVQ6c. This is of course not supported by Lenovo.
Unlocking the BIOS is definitely more like what you described. It's the price to pay for freely playing around with processor power limits, getting AES-NI instruction set support, etc. I have not checked since 2019, so there might be a clearer way.
There's also the W520, which looks like a T520, but is set up for a larger PSU, and had quad-core and better GPUs as factory options. (I own a few each of T520 and W520, but don't like the huge power bricks of the W. So I'm using the T as daily driver, until I really need something in the W.)
We could go back a little more and find a great PII 400. I had one with a CL 3Dfx Voodoo2 12MB, though I forget the 2D card.
It played MP3s REALLY well! As long as that is all you wanted to do because anything else would introduce skips and pops.
I like old machines, but I would hardly call them day-to-day usable with modern apps, and I would question the underlying hardware/firmware security the rest of the way.
If you're going to disagree, please give an example of something you think doesn't work.
Yes, if I don't have to keep multiple browser windows, video calls, Slack, and whathaveyou open, then I too can get by with an ancient Thinkpad. If it is enough for you, then all the power to you. I am sincerely supportive of the fact that you can stick it to today's consumerist, disposable tech industry.
Here I am on my T480s with 40 GB memory (8 is soldered) and the highest tier CPU for the Thinkpad gen (apparently these are soldered on too), and it's a drag. I'm trying to scrape by until I can start thinking about saving up for a new Framework.
That said, I maintain a G4 Cube running an outdated OS to play Sim City and Sim Tower. And it's "upgraded" as much as possible.
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