I've succeeded in flashing the D815EEA BIOS (version P10) onto my 4100!
I did some sleuthing. The .zip up above will not work: it is missing a couple files. I found the .exe to create a working BIOS floppy and have uploaded it as an attachment.
The instructions are similar to what's in the .zip:
- remove the BIOS jumper to set the machine to recovery mode,
insert the floppy and power on,
wait while while the drive grinds and then stops for a bit. You will hear 2 beeps.
Keep waiting, more drive activity follows. 2 more beeps.
Once it's done, hold the power button to turn it off,
unplug, remove the CMOS battery for 15 seconds, reinsert the battery and the BIOS jumper in its original position,
reboot.
It remains to be seen whether this is enough for Tualatins to work. I'm thinking more than likely. I've messaged the guy selling the pin-modded Tualatins just to be sure.
Pluto, the maxed out Dell Dimension 4100: Pentium III 1400S | 256MB | GeForce4 Ti4200 + Voodoo4 4500 | SB Live! 5.1
Charon, the DOS and early Windows time machine: K6-III+ 600 | 256MB | TNT2 Ultra + Voodoo3 2000 | Audician 32 Plus