Yeah, I started a new thread. Even though the topic's been posted so many other times/places/contexts, I figured this deserved a new one.
I've been working on this for a good while now, but simply don't have time to verify the procedure for myself (would have to rig up a DOS HD, run it, any complications would require more time to fix, etc.), but I think I know how to change/get rid of the BIOS boot image without firing up your hex editor...
The Award BIOS used here is very modular. It can accept things like standard VGA drivers, SCSI drivers, even some network driver support. The boot logo is a module as well.
First, grab a 256K image of the BIOS. I used AWDFLASH v7.52C, but newer versions should work as well. Try "awdflash /pn iopener.bin" to just get a copy of it w/o doing any flash operations at all.
Now that you've got an image, make a copy so if you screw up, you have a backup to work with.
Grab a copy of CBROM. Mine is CBROM v1.30 which supports the logo module. I've found it in archives called CBROM130.ZIP.
When you pull up the command options for this one, there are a few of interest: /D to display modules in the BIOS w/original filenames, /logo to manipulate the logo module. Displaying modules in the image is somewhat interesting; there's the base module, an "Other" mystery module, "YGROUP ROM", "VGA ROM", and "LOGO BitMap" (which also shows an original filename of 'welcome.bmp' beside it).
You can do 3 things with each module. Extract, Release, and Add. Extract dumps the module to a file. Release removes it from the BIOS (not, however, altering the size of the BIOS file). You can also put a new module file into the image.
I used "cbrom130 iopener.bin /logo extract" to get the logo out to a file, but Paintbrush and Photoshop don't want to open it. Not sure quite why that is. Probably has something to do with the fact that it's a binary module now, not necessarily an image.
"cbrom130 iopener.bin /logo release" removes it from the list of modules you get when you use "cbrom124 iopener.bin /D". This should disable the boot logo altogether -- this would be a very good thing for those who want unattended console OS booting (like me)..
"cbrom130 iopener.bin /logo tux.bmp" causes the program to do a little "..." status thing while it compresses the bitmap for use in the BIOS. After running the command, a "/D" shows the "LOGO BitMap" module with the filename changed to your input file. This should change the boot logo.
The bitmap used must be 640x464 (that's why you see the black bar at the bottom of NetP's boot logo), 16-color. I've also read somewhere or other that Photoshop puts a spin on the file format in such a way that it doesn't like to work with BIOSen. Try The Gimp instead. Or Paintbrush or Paint Shop or something.
Last step would be to flash the BIOS with the new image ("awdflash /py iopener.bin /sy"). This is the part I haven't tried yet. Things have gotten hectic, and I won't be able to try it for some time. It would be great if someone could confirm it for me.
Finally, some good BIOS sites are www.ping.be (Wim's BIOS page) and velociraptor.mni.fh-giessen.de/Bootlogo/ (in German, use babelfish). I figured out about 75% of the process, then found I had been preceded by some work on the above sites. =) Oh well.