You might as well do the BIOS flash first, that's what I would do 😀 It's very simple, too: just download the self-extracting .exe file that contains the BIOS, put the .bin file on a blank floppy diskette, put it in the 8RDA+'s floppy drive and reboot. At the POST screen, press ALT + F2 and it will automagically begin updating the BIOS from floppy with no further input from you. Wait 'til it finishes and you're all done. 😀
Oh, and SP1 should ideally be installed before you install the nForce motherboard drivers.