While PCI/AGP/PCI-E VGA cards use their own bios apart from the mainboard's bios, embedded video bioses can be found on all mainboards that use integrated chipsets like those from Intel, VIA, SIS, ALi and NVidia. Their mainboard's bios needs an additional module to enable the vga capabilities: the video bios. As on every vga card updated video bioses may help with display problems. A famous example is the missing WXGA display resolution on some SIS chipsets.
Since the mainboard market moves on much faster than it's been before most manufacturers quickly drop support for any of their legacy products. Updates - especially for integrated chipsets - are not available and might render an investment like a brand new WXGA 19" useless.
Finding a solution:
With the help of this step-by-step mini-HOWTO the average user should be able to replace a video bios of an integrated chipset. There are shell tools that enable direct access to the mainboard's bios modules including the video bios.
This HOWTO is not about making an integrated chipset a gaming machine or overclocking. It's not possible to upgrade any integrated chipset with a bios update in any way. If you're interested in those topics please look elsewhere instead.
Get the latest bios from your mainboard manufacturer first. If your problem still persists come back and read further.
An example on how to update a SIS 330 video bios (SIS 650/661/741/760) from version 2.03.00 to 2.49.00 on a Gigabyte GA-8S661GXMP with CBROM 2.07 will be shown. cbrom is a tool that only works for AWARD bioses. You may have to adapt video bioses and/or tools for your integrated chipset and bios accordingly.
Download and extract the latest bios for your mainboard with integrated chipset. Copy all files needed to a directory on your harddrive. Open up a command line interface and check if your bios can be edited with cbrom.
use the following command:
cbrom.exe <name_of_bios> /D
and something like this should show up. The name of the bios file is in this case: 661gxmp.f2
The vga bios of the integrated chipset can be found at number 6.
Extract the vga bios from the mainboard's bios and keep it somewhere in case something goes wrong.
cbrom.exe <name_of_bios> /vga extract
You will be promted for a filename. to keep the name used in the bios (203_6330.ROM in this case) just press return.
Remove the old vga bios from the motherboard's bios. CAUTION: if you remove any module from the bios it will simply be deleted without further prompting. That's why we made a backup copy in STEP 3.
cbrom.exe <name_of_bios> /vga release
to delete the old vga bios and make space for the new one.
Insert the updated vga bios into the mainboard's bios.
cbrom.exe <name_of_bios> /vga <name_of_vga_bios>
to inject the new version. The name of the updated video bios is SIS330.bin in this case.
Now flash the mainboard's bios and enjoy the updated video bios :)
DevCon - a command line tool to identify PCI devices with Windows 2000/XP/Server 2003 ((c) MicroSoft)
SIS video BIOS
SIS 65x/740 (aka Mirage/Real256/315/6325) v2.30.01 w/o 30x companion support
SIS 66x/741/76x (aka Mirage2/Ultra256/Xabre 660/330/6330) v2.49.00 w/o 30x companion support
SIS 67x/771 (aka Mirage3(+)/6350)
As cbrom is a DOS tool make sure all filenames do not exceed the 8.3 limit.
If you'll encounter problems regarding remaining space try to delete EPA patterns or build-in flash tools. Please run cbrom without options for more information. If you encounter other problems please report them.
Request for help
If you own a vga bios that you want to share with others contact me via personal message. Thanks for your help!