It's very likely an SPI EEPROM. I can't imagine a situation when you'd do something irreversible by rewriting its concepts, except:
- damaging the thing (e.g. by connecting power backwards or providing wrong supply voltage),
- flashing code that does something that damages the motherboard (I would expect that BIOS-code-that-damages-mobo is a thing, but it's very hard to accidentally mangle a BIOS into that form).