Doug Brown writes detailed posts on hardware hacking, retro Macs, embedded Linux kernel work, and repairing devices with reverse engineering tools.
HN commenters praise his Linux kernel porting series as excellent, and link his posts for hardware-specific and firmware debugging topics.
This same kind of thing happened to a family member several years ago on his Dell Inspiron 3650 minitower. Dell’s automatic updates installed a BIOS update (3.9.0) that bricked the computer. It would just power off and on automatically forever, no way to even access the BIOS. A bunch of other people online ran into the exact same problem.
I ended up reflashing the 3.9.0 BIOS to the flash chip and it fixed it [1]. Later on, people discovered that changing an Intel ME-related jumper on the motherboard also fixed it - a much easier fix.
It seems crazy to me that manufacturers include BIOS updates as part of automatic updates, especially for out-of-warranty systems.
[1] https://www.downtowndougbrown.com/2019/06/fix-dell-inspiron-3650-wont-boot-powers-itself-on-and-off-every-5-seconds/
That's the spirit! :-)
By the way, delving into obscure and hardware-specific kernel code, sometimes yields quite interesting generally-applicable problems. For example, @dougg3 did an (excellent!) series of articles about his work on bringing mainline kernel support to "Chumby 8", a somewhat obscure, but historically significant piece of hardware, and as a side-quest he stumbled into this:
https://www.downtowndougbrown.com/2024/04/why-is-my-cpu-usage-always-100-upgrading-my-chumby-8-kernel-part-9/
...which is applicable to quite a few other machines.
Intel has been absolutely incorrect on this a few times. Quite often there is a conflict in ranges that the ACPI spec included in the system firmware can't deal with, but if an operating system is clever enough it can work around the problem.
It may require some ACPI trickery, but it absolutely is doable. If the firmware guys are super lazy it may just work without ACPI trickery.
Check out an example here:
https://www.downtowndougbrown.com/2019/04/adventures-of-putting-16-gb-of-ram-in-a-motherboard-that-doesnt-support-it/