tiré de www.geforcefaq.com :
"Q. My card's Video BIOS is corrupted and I can't use my manufacturer's flash program to restore it. How can I restore it?
If you cannot get any display, get a PCI graphics card, put it in your system along with the GeForce, and plug your monitor into it. You should now be able to use NVFlash to reflash your GeForce's Video BIOS.
If you do not have a PCI graphics card spare, create a boot floppy disc on another system (select 'Copy system files' when you format it). Create a file called 'autoexec.bat' in the main directory of the floppy disc, and put the following line only inside:
nvflash -p -h -ffilename.ext
where filename.ext is the name of the BIOS flash file that you are going to use. Also copy nvflash.exe and dos4gw.exe into the main directory of the floppy disc.
Then put the disc in the drive and start the computer. The floppy disc should be read within 30 seconds or so. You should soon notice the keyboard lights going mad - this means that your video BIOS is being flashed. Your computer should reboot when finished, and hopefully your video card will then work.
If you want to get your original manufacturer's video BIOS back, try using WinAce to open your manufacturer's flash program file and see if you can extract the raw BIOS file from it. You can use NVFlash with this raw BIOS file. This has been tested with ASUS BIOS files.
You can download WinAce at the following website:
http://www.winace.com
Otherwise, you will have to find someone else with the same card and ask them to save their Video BIOS using NVFlash and then send you the file.
You can find out more about NVFlash in the 'Where can I get and how do I use NVFlash?' question."