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ReBarUEFI: Resizable BAR for almost any UEFI system

89 pointsby nateb2022last Monday at 1:07 AM28 commentsview on HN

Comments

zir_blazertoday at 12:58 AM

These kind of BIOS modding shenannigans is why I got interesed in Coreboot, so that enhancing a Firmware capabilities becomes possible without touching propietary tools/code.

Other similar mods included adding NVMe Boot capabilities to older Firmwares that didn't supported them so that you could boot from modern NVMe drives if you used some kind of adapter (As none of those Motherboards have M.2 Slots, but you can use them with a PCIe-to-M.2 adapter card). Also adding required stuff to get certain CPUs booting in Motherboard that were never officially supported (Depending on generation, could be as simple as adding new CPU Microcode).

gregoryltoday at 3:31 AM

Tempted to see if this will work on the work dell laptop, which hardware supports rebar, but Dell just can't be assed to enable it - use an external ARC GPU to properly support 3 screens (again, Dells awful drivers / firmware - the same hardware supports 3 screens just fine).

marcus9999yesterday at 11:26 PM

this fixes a real annoyance on older workstation boards where above 4g decoding is a requirement but the option isn't even in the bios menu. saw a build recently on an x79 board where it had to be exposed with a hand patched bios before anything like this or a modern gpu would work at all.

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bigwheelsyesterday at 11:05 PM

What does this do? I perused the README but I'm still clueless on what the purpose and use-case is for ReBAR.

(Posting this under the assumption others will also appreciate a bit of quick context.)

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suprjamitoday at 2:26 AM

I am in need of this from the opposite direction - an RTX 3080 20G BIOS which adds ReBAR to the card.

Claude tells me the BAR is outside the encrypted part of the card firmware so theoretically should be possible?