That still doesn't answer the question of why it's better. Unless you're paranoid about an OEM backdoor, I think this is cool but not worth the effort.
I think firstly is the FOSS obsession and backdoor paranoia from evangelists, and secondly and the more practical one is that the proprietary IBM BIOS is full of bugs and anti-consumer blacklists and whitelists designed to limit repairability and upgradeability, which stil boggle my mind on how those laptops got such a good image on that front.
I wonder if this can help with the extremely irritating bug (intentional?) on the X270 where if you give it a third party 9-cell battery, it will raise CPU_PROCHOT all the damn time, and my processor would drop to below 1Ghz clock speeds.
Back when I used to have an X270 I had a shell script that ran on boot which poked a register to disable thermal throttling handling. Not at all ideal, but it made the machine usable in the absence of official Lenovo batteries which they stopped manufacturing pretty damn quickly.
I was the happy owner of ThinkPad X1 Extreme g1. It had that bug out of the box, new original battery. Once it thermal throttles, it never goes back to full GHz. It throttled pretty soon, cause big CPU small chassis. Yes, I had a script like that.
It is still somewhere on a shelf, so maybe its day will come again.
Nice to finally know what was happening to my x270 after so many years. Well good thing it doesn't happen when connected to power nowadays is my home server
Possibly. Usually this is handled by the embedded controller, and not sure if that was reversed or not. You may be able to tristate the GPIO line that tells the CPU that a pin means PROCHOT, which would allow you to ignore the ECs attempts to do this.
because the x280 and x270 are similar enough I didn't need to try very hard to get it to post or boot a live USB to further investigate (effectively acting as a decent template for me to work off of)
The console viewing itself was provided by `cbmem -1`, which I could run via a NixOS live USB with nixpkgs#coreboot-utils
You can sometimes find the serial lines if you are careful. Otherwise you can use the flashrom to store the output, and read it back out after each failure. It is much easier to just poke around and find the serial if you can, either from schematics (it seems the author has these) or by hand with a lot of patience or board scrying.
pretty cool work!
Though it leaves me wondering if coreboot/bios code can directly interface with thermal-management and battery controller , shouldn't it be feasible to improve upon battery life by exposing some interface to OS, like apple laptops ?
The PROCHOT discussion in this thread is a good example. Lenovo stops making batteries, third party ones trigger artificial throttling, and the only fix is poking registers with a boot script. With coreboot you can just... fix it properly.
More broadly: faster boot times (sub-second POST is common), no vendor bloat or hidden phone-home behavior in the firmware, and you can actually audit what runs before your OS loads. That last one matters more than people think. Your BIOS has full access to everything on the machine before any OS-level security even starts.
> I can’t recommend libreboot enough, or even heads if libreboot isn’t your speed.
Why though? Not a single reason mentioned in post about why would it be better than whatever stock BIOS the laptop is shipped with.
It replaces a proprietary component of your system with an open source one.
Reading https://libreboot.org/#why-use-libreboot might provide further enlightenment.
That still doesn't answer the question of why it's better. Unless you're paranoid about an OEM backdoor, I think this is cool but not worth the effort.
I think firstly is the FOSS obsession and backdoor paranoia from evangelists, and secondly and the more practical one is that the proprietary IBM BIOS is full of bugs and anti-consumer blacklists and whitelists designed to limit repairability and upgradeability, which stil boggle my mind on how those laptops got such a good image on that front.
The goal of that blog post is not to sell you something.
This can be confusing on HN, I know.
A recommendation without context is pointless. A recommendation with context could be very helpful!
I wonder if this can help with the extremely irritating bug (intentional?) on the X270 where if you give it a third party 9-cell battery, it will raise CPU_PROCHOT all the damn time, and my processor would drop to below 1Ghz clock speeds.
Back when I used to have an X270 I had a shell script that ran on boot which poked a register to disable thermal throttling handling. Not at all ideal, but it made the machine usable in the absence of official Lenovo batteries which they stopped manufacturing pretty damn quickly.
I was the happy owner of ThinkPad X1 Extreme g1. It had that bug out of the box, new original battery. Once it thermal throttles, it never goes back to full GHz. It throttled pretty soon, cause big CPU small chassis. Yes, I had a script like that.
It is still somewhere on a shelf, so maybe its day will come again.
Nice to finally know what was happening to my x270 after so many years. Well good thing it doesn't happen when connected to power nowadays is my home server
Oh almost certainly. PROCHOT is programmable.
Possibly. Usually this is handled by the embedded controller, and not sure if that was reversed or not. You may be able to tristate the GPIO line that tells the CPU that a pin means PROCHOT, which would allow you to ignore the ECs attempts to do this.
Do you think it could also be due to an ACPI table?
Its possible. I know from the BIOS revision changelogs that the T470 did get a patch to fix this, but the X270 never did.
Thinkpads do same thing when detecting 65W supply instead of 90W despite you only need 90W if running full tilt while charging.
How did OP debug this without a serial port?
I’ve messed around with porting coreboot on two desktop platforms but always had the benefit of a HW serial port…
because the x280 and x270 are similar enough I didn't need to try very hard to get it to post or boot a live USB to further investigate (effectively acting as a decent template for me to work off of)
The console viewing itself was provided by `cbmem -1`, which I could run via a NixOS live USB with nixpkgs#coreboot-utils
You can sometimes find the serial lines if you are careful. Otherwise you can use the flashrom to store the output, and read it back out after each failure. It is much easier to just poke around and find the serial if you can, either from schematics (it seems the author has these) or by hand with a lot of patience or board scrying.
pretty cool work! Though it leaves me wondering if coreboot/bios code can directly interface with thermal-management and battery controller , shouldn't it be feasible to improve upon battery life by exposing some interface to OS, like apple laptops ?
I always wondered, what is the practical advantage of running coreboot on my laptop?
The PROCHOT discussion in this thread is a good example. Lenovo stops making batteries, third party ones trigger artificial throttling, and the only fix is poking registers with a boot script. With coreboot you can just... fix it properly.
More broadly: faster boot times (sub-second POST is common), no vendor bloat or hidden phone-home behavior in the firmware, and you can actually audit what runs before your OS loads. That last one matters more than people think. Your BIOS has full access to everything on the machine before any OS-level security even starts.
Atom feed is malformed :(
sorry, I'll look into it
This is absurdly trans-coded.
Ah, todsacerdoti. ;)
I am a trans woman, yes :o
(the user who posted my blog post is not me :p)
What I would give for a wife that would enjoy tinkering with me.
Seek and thou shalt find. Just don’t be too pushy on the romantic side of things.
Too late for me then I suppose, I'm married with two kids.
This gave me a good chuckle :)
Was AI Used?
Hi! As the author, no! I take a hard line stance against AI use myself. It's just not for me.
Respect.
Does it matter?
on HN in 2026, I’d say it’s never mattered more lol
HN? You mean Molt News?