1. I'm not sure and your link didn't work for me anyway.
2. I'm not sure if it even matters and your link doesn't work for me anyway. If I had to guess, I'd say that I'd expect a reference card tobe better off with a reference BIOS from AMD, but I make no guarantee on that.
3. Again, not sure if it matters and again, your links don't work for me.
Furthermore, whether or not you asked for them, I'll say this anyway. There is no good reason to get a GHz Edition BIOS because it is inferior to the regular BIOS. The only advantage is the Boost feature and higher stock clocks, but they come at the cost of an otherwise inferior BIOS and even more unnecessarily high stock voltages. The allure of a 7970 GHz Edition is that it is generally using better binned components than the regular 7970, not the crappy BIOS. You could easily get better performance and power consumption out of manual overclocking.
Thanks for your honest answer, that you never did a bios flash!!
I think is important to have some experience in flashing to give a advice inhere.
I did find another great tutorial now I only would like to know what is the best Bios, which because it is a reference card, I think it must be the one from ATI. Bios from Sapphere could be also from a special design and then I have a problem.