This isn`t my work - just translation.
Author is xKVtor from overclockers.ru forums. You can find original article in russian here.

With this tutorial you can learn how to make single BIOS screenshot and save it to FloppyDisc. You will need any PCI PATA/SATA or RAID controller from SiliconImage. All required files are located in this archive.
It contains:

BIOSes
modded BIOSes for SiI0680 and SiI3112 controllers (not real BIOSes, just the code required to make SS - so you won`t be able to use devices as PATA/SATA/RAID controllers).
To use any other controller from SilImage you have to :
  • change VendorID (1095h - SiliconImage) and DeviceID (0680h, 3112h) for required one;
  • modify checksum, so the controlsum of pseudoBIOS (first 512 bytes) would be equal to 0.


Utilities
Utilities kit that reads taken screenshot from floppy and converts it to BMP pic.

So here`s the instructions :

  1. Flash pseudoBIOS with UPDFLASH.EXE in controller you have. Be sure to save original BIOS.
  2. After flashing reboot your system and enter BIOS setup. To make screenshot just hit PrintScreen button.
  3. Then go into Windows and run _RunAll.bat file from Utilities folder. After bat file has completed it`s work you`ll find new RES.BMP file in the same directory which is actual BIOS screenshot. And this is screenshot of all BIOS page, not only part you can see on monitor.


Here`s example of screenshots taken with digital camera and actual screenshot made with this tutorial:



Do rember that you can save only one screenshot to floopy that was taken with last hit of PrintScreen button. But you can use several floppy discs.
Do format floppy disc(s), cos previous information will be damaged.

Bugs found during test of this method:

  • Several motherboards (usualy Asus) with onboard video adapters cannot save screenshot - you will get white pic.
    Also this is what was made on ASUS P5GD1 Pro rev. 105:

  • Some BIOSes (like one on Epox 8KHA+ author used) doesn`t switch to PCI cards` BIOS control before entering the BIOS. So you cannot make screenshot on these motherboards with this method.
  • There are some exotic looking BIOSes with their own colors and different video modes and this method also might not work.
  • While there`s PCI card with pseudoBIOS in your PC there is a risc to corrupt floppy disc by accidental PrintScreen button hit while in BIOS or in DOS (both original and one in Windows).
  • If you don`t want to get this picture :



    be sure to hit PrintScreen button twice (in the same BIOS page of course).


Conclusion
Of course taking screenshots with camera is alot easier and faster. But if there`s somebody who can make similar app so it could be integrated into motherboard`s BIOS and use USB flash drive to save as many as you want screenshots to it already in BMP - go for it.

P.S. I myself haven`t tryied this one yet.
Or and all above mentioned you do AT YOUR OWN RISC !
Me nor XS nor author of this tutorial doesn`t take ANY responsobility for damages that might accuire.