Just tried again after loading the Optimized Defaults and deactivating the anti-virus.
From @BIOS the only available update was F10.
I downloaded this from the first server in Taiwan.
This installed fine and told me to reboot the PC to finish,which I then did.
I then went back into the BIOS and reloaded the Optimized Defaults.
Back in Vista,I ran @BIOS again and ticked the box next to Find BIOS from GigaByte and clicked Update New Bios.
I selected each server in turn (servers 1 and 2 in Taiwan,China,Japan and USA) and each one would only find the F10 update.
Unchecking the box and selecting my own previously downloaded F11 file (of which I have 3 different versions) resulted in the progress bar reaching 100% before the ""BIOS Partnumber(AWARD) is not correct"
Sorry,there is no indication of any checksum message.