What BIOS Updates?

For the past few days, I've been debugging an issue that causes one of the two more-or-less-identical NICs in a new server to fail with code 10 ("the device failed to start", which is just about as vague as you can get). Internet searching suggested that I should upgrade my BIOS. Fair enough.

The manufacturer of the BIOS in question is American Megatrends, who have a large section of their web site devoted to talking about how great their BIOS/UEFI ROMs are and then proceed to not let me download them. Links to the BIOS upgrade tool are all over the place, but it seems to be only a program that lets me do the burning - no actual replacement ROMs come in the ZIP file. (But it does give me a DOS version of the program, so I can flash my BIOS on DOS. If I had DOS. Or a BIOS ROM to flash.)

Further Internet searching ensued, and I found links to download a big ZIP of different ROMs, varying based on motherboard. (It's a Foxconn G[something or other]-K.) The only issue was that all those links pointed to pages on the American Megatrends site, all of which silently redirected me to their home page but kept the URL same-ish, just enough to confuse me for a moment.

I still have no idea how to actually update this BIOS.