Hey, I'm trying to install Solus 4.1 MATE on my Lenovo Legion Y540 laptop and I am getting BIOS errors on boot up of my USB with the installation media.
You should be more specific, what errors? One easy thing you could try to check if Legacy Boot is set to on or off. If you disable it you will force the system to boot in EFI mode (instead of BIOS), which should be the default for all modern hardware.
I've set it to be Legacy with the default being UEFI first it doesn't boot at all, with Legacy and Legacy first it boots, get another similar screen of errors then it boots like it should with the green and white Solus text of everything being initialized and it does boot up to MATE fine.
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