Most times is not only a BIOS issue, but a hardware too. Console BIOS are usually heavily encrypted, so no mod are possible without expecting secondary effects (blinding moding). If someone try to re-write a BIOS, and fails, could make the mainboard to autokill hitself (see CPS2/3 (Capcom Play system 2/3) principle for most details). Console BIOS are not prepared to be changed by users, like a PC, and considering it is the heart of its protection, expect lots of anti-cracking countermeasures here.

morg