BIOS Flash Failed Dell 9100

Why did you have to flash the BIOS?  Was there a particular issue you needed fixed that required a BIOS Update?

Is yours a Dell DIMENSION 9100?  You just described it as "Dell 9100".

If so, there are two methods to flash the BIOS, as indicated on their support page:

http://tinyurl.com/8t6f9

Method 1:
-----------
Run from Within Windows:
http://tinyurl.com/9frqu

You did this, and the process was interrupted, so you have half-baked instructions on the BIOS Chip.

That's the problem with flashing the BIOS from within Windows.  There's too much that can go wrong, and the Windows versions don't always provide the option to create a backup BIOS data file.  From what I can see of the update file you used, it DID offer this option:

Loading ROM image
Saving image file <-------
File %s written.

Method 2:
-----------
Run from a bootable floppy:
http://tinyurl.com/9ogm4

Do this, and it should write the proper instructions onto the BIOS chip from scratch.

http://ftp.us.dell.com/bios/D9100A02.EXE (498 KB)

Info about this BIOS Version:
---------------------------------
The following changes have been made to BIOS rev A01 to create A02:
1. Updated microcode for newer CPU steppings.
2. Updated SMBIOS tables to meet new specifications.
3. Improved USB support.
4. Improved BIOS flash support <------ So the flash support in A01 was BAD then??

>>>
Instructions:

Run the BIOS update utility from DOS environment (Non-Windows users)

NOTE: You will need to provide a bootable DOS diskette. This executable file does not create the DOS system files.

1. Copy the file D9100A02.EXE to a bootable floppy.
2. Boot from the floppy to the DOS prompt.
3. Run the file by typing
    A:\D9100A02.EXE
   where A: is the drive letter where the executable is located.
<<<

OK, so you are wondering about DOS and the fact that Windows XP doesn't use DOS, etc, etc.  All you need is a very basic boot floppy that loads the barest of DOS files needed to run the program.  The DOS files don't have to be copied to the hard drive or anything, they are only loaded into memory and your Windows XP operating system isn't loaded at all.  Your operating system is DOS, and the boot drive is the floppy.

Problem 1:
------------
Do you have a floppy drive in the Dell Dimension 9100?
Looks like it was optional:
http://support.dell.com/support/edocs/systems/dim9100/en/D86630LRs.pdf
If not, buy one and install it.

Problem 2:
------------
How to make a basic boot floppy to run the update file D9100A02.EXE?
http://www.bootdisk.com
Looks like any of these will suffice:

http://download.sudhian.com/faq/kt7/downloads/Misc/drdflash.exe
http://www.abitfaq.it/Files/drdflash.exe
http://k7jo.de/tools/drdos/drdflash.exe

Info about the boot floppy:
http://www.bootdisk.com/txtfiles/bios.txt

Just run the "drdflash.exe" file on any Windows system with a blank floppy in the drive, and it will create a boot floppy that boots into DRDOS.  Copy D9100A02.EXE onto the floppy.  Create a copy of AUTOEXEC.BAT on the floppy and rename it TEST.BAT.  Right-Click and open it in Notepad for editing.  Change it so that it reads:

@echo off
cls
echo this is the batch file named test
exit

and save it.

Before running the BIOS Update again, make sure the system boots to the floppy.  When it stops at the prompt, just type the command   TEST   and ensure that it shows that line of text on the screen: ie. "this is the batch file named test".

If that worked, then you have two options:

1. Boot to the floppy and type the command   D9100A02.EXE  (the .exe is optional)
2. Modify autoexec.bat so that it just runs  D9100A02 as it boots.

Autoexec.bat can just be changed to:

@echo off
cls
D9100A02.EXE

Just be sure to read all the instructions very carefully.  It's too late to save a backup of your BIOS to the floppy now, as yours has been screwed up, but that would be one of the options.

Good luck.