No need to flash anymore. MSI's afterburner unlocks the upper limits on all HD 5000 cards that support voltage tweak without requiring a bios flash.
Some people might be unlucky enough to have a non reference 5770 which doesnt have the voltage tweak chip at all, and flashing those to a reference card bios may end up bricking the card.
If MSI afterburner doesnt work on your HD 5000 card, DONT bios flash it.
Thanks for the warning! will keep this in mind, afterburner doesn't give me voltage control at the moment, do i have to unlock unnofical overclocking before it shows up?