The download file I see is P4S800_06.zip (214251 bytes). It contains
Group2.ROM 35696 bytes
P4S800_06.AWD 262144 bytes (256KB exactly)
The AWD file is the one that you use to program the flash. I have no idea
what the Group2.ROM file is doing in there. That file corresponds to a
subsection of the .AWD file, but I don't think that has anything to do
with flashing the BIOS. The manual claims the board has a 2Megabit
flash chip, so a 256KB file just exactly fills it.
I would rename the file, to fit a DOS 8.3 naming convention, like
P4S80006.AWD .
So, first off, have you verified that your floppy works ? If you have
a utility that can do a checksum on a file, you might check that the
checksum of the file, as copied to the floppy, matches the checksum
of the file where is was unzipped on your hard drive.
If you cannot get EZFLASH to work, there is always AFLASH221, which
is listed on the download page:
http://www.asus.com.tw/support/download/item.aspx?ModelName=P4S800&Type=All
There are instructions in the manual for that, and the toughest part
will be getting your OS to make a bootable floppy diskette. Make sure
to back up (make an archival copy of) the BIOS currently stored in the
flash, in case there is a problem with the flashing operation, you
can immediately try to reflash with the original flash file. There
should be room on your bootable floppy for both the archived flash file
and the new flash file at the same time.
HTH,
Paul