Tutorial written by : Unreal7000
Last edited: August 22, 2003

Requirements:
-Xbox with an installed mod-chip - X2, Matrix, etc
-XBTool (here)
-Evo-X Dashboard - installed of course
-BIOS that you want - I used X2 4976.02 but you can use whatever you want, can't tell you where to get it sorry (X2 4977 is the latest at time of writing I recommend getting that)
-Punching Bag (Optional) - Don't worry this is only if something goes wrong.

WARNING: If you do this wrong you could ruin your mod-chip. Neither I nor xbox-scene.com or any affiliates are responsible for the damages that could take place.

Now that we got that out of the way we can get to the fun stuff!

This is the story of how I flashed my mod-chip (X2 lite) from BIOS X2 4973 to X2 4976.02. My mod-chip maybe different than yours so research is always your best-friend.

Once you have downloaded your BIOS (.BIN format) you will want to open it up in XBTool.
First thing that you will want to do is verify the BIOS MD5. This is located at the top of the program. To do this look go to
http://forums.xbox-scene.com/index.php?act=ST&f=38&t=43437
see if the BIOS you are using has the same numbers and letters as the one on that site(I think they're HEX).

So lets say you have a virgin 1MB X2 4976.02 BIOS, make sure the hash marks are identical (usually if the first 5 or 6 numbers match then your golden, but just make sure they all match).
From here you are free to change the colors or remove animation etc in XBtools.
These are completely optional and I recommend NOT doing these options the first time, unless you just really want to. Its your own funeral. If you are making NO changes (Means BIOS is the correct SIZE and everything) then you dont need to save it.

Once you have made the wanted changes make sure you match the "file size" with the maximum that your mod-chip supports. Example: The X2 comes with a 1MB BIOS. But the Matrix comes with 256K.
You can see what size your BIOS supports here: http://www.xbox-scene.com/modchips3b.php
Once you have double checked everything hit "Save As" and name it something so that you will remember. Example: "Xecuter 4976.02 Orange NoAni 1MB" (Orange Boot up and No animation) or "Xecuter 4976.02 Virgin 1MB". Again, if you are making NO changes (Means BIOS is the correct SIZE and everything) then you dont need to save it.

Now you will want to FTP into your Xbox and go to the C drive, if there is not a folder called "Bios" then make one. Once thats done put the BIOS that you will use into that folder.
Check your evox.ini file to make sure you have somthing in the "Menu" part that looks like this Item "Flash BIOS",ID_Flash_Bios.

Section "System"
{
Item "Settings",ID_Settings
Item "Flash BIOS",ID_Flash_Bios
Item "Backup",ID_Backup
Item "Skins",ID_Skins
}
Item "Reboot",ID_Quick_Reboot
Item "Power Off",ID_Power_Off

If the the "Flash BIOS" turns red and won't let you access it, then change it to Item "Flash BIOS",@1

The next part is optional but i highly recommend it.
If you look around in the evox.ini file you will notice some lines that look SIMILAR to this:

[BIOS]
#
ROM = "Bluecop 4627 Debug",0x844ff9e0fc7f7bd01ec5e75b10aece62
ROM = "CPX 1.02 Debug no ani",0xAC65F68F2706235A578FE1C5FB1E41B1
ROM = "CPX 4034",0xcf36ad116e2404aff022533b07b11004
ROM = "CPX v1.0 Debug",0xfd1ac8ba0033df93e2da2a23009272e4
ROM = "CPX v1.0",0x4132e24c64b7a8d4ea34ff448051e923
ROM = "CPX v1.02 Debug no ani",0xAC65F68F2706235A578FE1C5FB1E41B1
ROM = "CPX v1.02 Debug",0x8E5C811CCC3C6875FD90C4D0ED6A8ABF
ROM = "CPX v1.02 kina",0x84efef3ee91ac320dab4778881108938
#

This is a database of how EvoX recognizes what BIOS you are using.
I recommend going back to
http://forums.xbox-scene.com/index.php?act=ST&f=38&t=43437
and copying all of it and replacing it with what was in [BIOS] or you can add it to what was already there. However, lets say you customized your BIOS and it doesn't match any of them that are in the list. You can make your own. Heres how:
ROM = "BIOS Name",hash
where "BIOS Name" is where you fill in what you want evo-x to say.
Example: "Xecuter 2 4976.02 blue noani 1MB"
Hash is the hash of the BIOS. To get this fire up XBTool and open your customized BIOS and copy down the BIOS MD5 hash. (No need to save since you aren't making changes) Make sure you put the 0x in first.
Now Evo-X will recognize what BIOS you have and will display it in the settings.

On a side note some people have told me that you may also need something like this in your evox.ini file (check and see if something similar is there):

Flash = 0x01d5,"AMD - Am29F080B",0x100000
Flash = 0x04d5,"FUJITSU - MBM29F080A",0x100000
Flash = 0xadd5,"Hynix - HY29F080",0x100000
Flash = 0x20f1,"ST - M29F080A",0x100000
Flash = 0xbf61,"SST - 49LF020",0x40000

Now comes the worst part of all. I do not recommend doing this during a storm, rolling blackouts, or whenever there is a chance of the power going out. If for some reason you turn-off or lock up the xbox while it is flashing or erasing the BIOS then you will need the dreaded Punching Bag.

Go to your xbox and turn it off. Open it up and disable the flash protection. For Matrix owners put it in mode 4, both dip switches OFF. Put xbox back together and turn on. Now go to "Flash BIOS" and hit X. you should see your customized BIOS. Hit X and then it will say something on the screen that says "Press Y to flash" press Y and ONLY press Y if you have double checked and researched everything. Once you hit Y it will go through the process of erasing and installing your new BIOS. The whole process takes about 20-30 seconds. Afterwards it will say "Your Xbox will power off" Wait till it powers off and with fingers crossed turn on your Xbox and you should see that it is working. If not pull out Punching Bag and hit repeatedly until you feel somewhat better. If for some reason a bad flash did occur and you own a X 2.X lite/lite plus your not all that much out of luck, for around 15$ you can buy a programmer that hooks up to your PC and allows you to flash it from there. http://shop.system-mods.com/product.asp?3=95
If for some reason you get an error when you try to flash or it locks up in the middle of the flash process, there is a 99% chance you forgot to remove the flash protection. I can't tell you how many time people have instant messaged me with this question.
If it is booting up then go to the settings of Evo-X and scroll down to see if it recognizes what BIOS you have installed. If it says "Unknown" then you can either ignore it or you can read what i wrote above. I like to have it display my BIOS that way if I forget. Now you can open back up your xbox and put the flash protection back on (dont want little kids accidently flashing your BIOS now do you). You can either keep the Bios that you put in your Bios folder in the C drive of your Xbox for future use or you can delete it. It is no longer required for your Xbox to work.

I recommend reading this thoroughly, and doing some research for your mod-chip. Did someone say Google? Please do not instant message me asking for the BIOS because im sick of responding to those messages.

Thanks to Dink for telling me about the Flash part in the evox.ini file.
Thanks to Katana-Sama for filling me in on information about the Matrix mod-chip.

Happy Flashing
Samuel Dockery (Unreal7000)