Compare to my server-class Tyan motherboard. There are huge problems with IPMI on this system (basically it doesn't work at all), but in order to flash the BIOS to possibly fix it, I need
1) a floppy drive (on a modern server?! WTF?)
2) Windows: they say FreeDOS 'may' work but only Windows is 'supported'.
3) a lot of luck: the flash images are specific to your particular sub-brand of motherboard or something (possibly even the batch number); this info is not easy to determine, the various images are not clearly distinguished from each other, and the flashing tool doesn't check to see that you're installing the right version
If the flashing fails (and googling suggests that this is not uncommon, not surprising given the info above), your BIOS is toast and you have to send it back to be replaced, only Tyan say they refuse to accept replacement requests from customers and you must go through your OEM. i.e., if your machine is out of warranty, or if it's *in* warranty and your OEM aren't nice guys, you're dead and your umpty-thousand-quid server is toast.
Oddly I have decided to live with whatever BIOS flaws this system may have. I can live without IPMI.