https://www.techpowerup.com/225214/p...-480-red-devil

PowerColor today released an optional "Unlocked BIOS" for its Radeon RX 480 RED Devil graphics card. Available through PowerColor DevilClub (and TechPowerUp), the BIOS is optional because it is intended only for power-users. The BIOS increases power-limits on the card, facilitating higher overclocking headroom and clock speed sustainability.

The obvious trade-offs here are higher power-consumption, temperatures, and noise. In fact, PowerColor strongly recommends against using the modded card with FurMark as the company found that it will damage even non-overclocked cards with the new BIOS. PowerColor, however, stated that flashing your card with the optional BIOS will not void your warranty.
https://www.techpowerup.com/vgabios/...80-8192-160803