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Hey,

I am looking for some cheap models of laptops with 32bit EFI.
Could you recommend anything?
I need one for experiments and the only requirement is 32bit UEFI.

prontoguy wrote:Hey,

I am looking for some cheap models of laptops with 32bit EFI.
Could you recommend anything?
I need one for experiments and the only requirement is 32bit UEFI.

These are pretty unusual. I only know of one (rather dated) CPU board that has 32-bit UEFI. It's currently end-of-life. Newer hardware always comes with 64-bit UEFI since the CPUs used support long mode, and older one's typically only have BIOS boot.

If you want to boot a 32-bit OS from 64-bit EFI, it's possible to switch the processor back into protected mode and real mode.

I think some firmware will boot the OS in 32 bit protected mode if they find BOOTIA32.EFI, but I could be wrong.

TBH, 32 bit EFI is very rare, hence I wouldn't worry about it that much.

bootia32.efi <<< for you 32 bit efi app
bootx64.efi for your x64 efi app ;


you dont need to worry about 32/64 bit ; efi itself will recognize if you put 32bit app ; it'll be 32bit app; if you put 64 ; it'll be regarded as 64bit ;

nexos wrote:I think some firmware will boot the OS in 32 bit protected mode if they find BOOTIA32.EFI, but I could be wrong.

I very much doubt that. I provide both bootx64.efi and bootia32.efi, but all firmware will boot using bootx64.efi (except for the one that runs 32-bit EFI only). OTOH, I have not tested what happens if I remove bootx64.efi.

But do you know a hardware that provides 32bit only EFI? Could you provide some examples?

Early Intel Macs have 32-bit EFI, including some that have 64-bit CPUs. They're different enough from ordinary PCs that this may not be what you want, though.

I found this very incomplete list of devices that are known to have 32-bit UEFI.