Doug Brown
downtowndougbrown.com · Personal blog · on HN since 2019
Doug Brown writes detailed posts on hardware hacking, retro Macs, embedded Linux kernel work, and repairing devices with reverse engineering tools.
What HN saysHN commenters praise his Linux kernel porting series as excellent, and link his posts for hardware-specific and firmware debugging topics.
20HN people shared it
3linked it in comments
64stories submitted
5.7Kstory points
10 months agolast shared
2019people per year2026
Most-shared posts
- 1Adventures of putting 16 GB of RAM in a motherboard that doesn’t support it3 people · 1.2K points · first shared 2019 · 178 comments on HN
- 2Why is my CPU usage always 100%?3 people · 540 points · first shared 2024 · 143 comments on HN
- 3Customizing the startup chime on a 1999 G3 iMac3 people · 6 points · first shared 2023 · discussion on HN
- 4Apple's developers reflashed Mac ROMs in the '90s3 people · 5 points · first shared 2023 · discussion on HN
- 5Upgrading my Chumby 8 kernel part 4: reboot/poweroff3 people · 3 points · first shared 2023 · discussion on HN
- 6Fixing an Elgato HD60 S HDMI capture device with the help of Ghidra2 people · 515 points · first shared 2024 · 96 comments on HN
- 7Playing 1080p H.264 video on my old 256 MB Raspberry Pi2 people · 10 points · first shared 2024 · discussion on HN
- 8Hardware repair of an Elgato HD60 S that only worked on Mac2 people · 5 points · first shared 2024 · discussion on HN
- 9Upgrading my Chumby 8 kernel part 3: Wi-Fi2 people · 2 points · first shared 2023 · discussion on HN
- 10Upgrading my old Chumby 8 Linux kernel part 1: U-Boot2 people · 2 points · first shared 2022 · discussion on HN
- 11Getting ChatGPT to write a Linux kernel module for me2 people · 2 points · first shared 2022 · discussion on HN
- 12The capacitor that Apple soldered incorrectly at the factory1 people · 536 points · first shared 2024 · 259 comments on HN
- 13Finding a 27-year-old easter egg in the Power Mac G3 ROM1 people · 394 points · first shared 2025 · 120 comments on HN
- 14Apple's long-lost hidden recovery partition from 1994 has been found1 people · 315 points · first shared 2025 · 99 comments on HN
- 15An invalid 68030 instruction accidentally allowed the Mac Classic II to boot1 people · 304 points · first shared 2025 · 69 comments on HN
What HN people wrote when they linked it
kees99 · 2025-10-09
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-1…
...which is applicable to quite a few other machines.
dougg3 · 2024-06-06
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-…
ungamed · 2022-02-28
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-…