BIOS update may or may not be needed, even down to the motherboard revision.
I just built a PC around that CPU. Gigabyte mb. At the site, it specifically said a BIOS update 'may' be needed. It wasn't, for that particular revision I got.
Look at their website. Look into what BIOS version supports that CPU. When was that BIOS version released? That may give an indication of whether you will need an update or not.