Personally I wouldn't update a gpu bios if I wasn't having an issue and/or the new bios didn't add new features. In this case I definately wouldn't update the bios until Gigabyte come out with something that actually works for all.
Given that you're running yours on a PCI-E 2.0 you probaby wouldn't realise if you had a faulty card.
Given that you're running yours on a PCI-E 2.0 you probaby wouldn't realise if you had a faulty card.