Woah, that’s some serious care going into the “ugh it’s 1.8V” problem. When I recovered my previous board (X370) I just used a 5V-3.3V shifter module – plugging 3.3V into the “5V” side resulted in 2.8V on the “3.3V’ side which was “a bit better”™ so I used that. Surprise, the flash didn’t care. Seems like these chips are unofficially 3V tolerant and you can just YOLO it with a direct 3.3V connection.
Also my board had a 2.0mm pitch SPI header and I didn’t have connectors for that back then (nor did I have a chip clip). I, uh, managed to fit some 2.54mm connectors on the pins – couldn’t connect all pins but it still worked (at a low speed) without GND.
Wow! That’s impressive! There’s “hacking,” and then there’s “I’ll remember you and never let you anywhere near my computer!” ;)
Nice that the Bios wasn’t some .exe file like they so often are.
yeah that part surprised me as well. when i figured out that they would be flashing it with a chip clip (before they said they were doing that), my first thought was “i wonder how they will deal with the exe bios blob from the board oem…”
These are often self-extracting archives. e.g. for Lenovo you just use innoextract.
But with desktop boards you’ll see a very easy way to get the raw EFI capsule far more often because 1) they typically have a flasher in their setup screen that lets you load the capsule from storage and 2) the higher-end ones also have CPU-less flashing where you press a button and it automatically picks a capsule from a USB flash drive in the marked slot.
the higher-end ones also have CPU-less flashing where you press a button and it automatically picks a capsule from a USB flash drive in the marked slot.
Yeah the article mentioned that, and it’s the first time I’ve ever heard of that feature. Sounds really useful and hopefully support for it more widespread in the future. (I guess it’s using the intel ME or amd’s PSP thing?)
No, the PSP would not even try to start without the CPU present… because uhh it’s on the CPU die (Zen is basically a full SoC, AFAIK some server platforms exist that are completely chipset-less) and its firmware is inside of that SPI flash.
ME is/was (??) physically on the PCH but the firmware thing still applies.
This is definitely done with a custom microcontroller.
Speaking of features, there are also boards with “dual BIOS”, either manual or automatic switching between two SPI flash chips. (And doing automatic without a physical switch to turn it off is a great way to make overclockers hate your stupid board!)