your listed bios J63_0396.bin is for a z820, not a z800 see below for the z800 bios
for previous bios's select windows 7 32 or 64 bit then select the BIOS link to expand, it will show the latest (3.61 revA)
THIS IS THE ONLY ONE YOU NEED TO USE, PREVIOUS VERSIONS WILL NOT CORRECT A IMPROPER FLASHING METHOD
the directions below are just to point out that additional information can be found by clicking those blue triangle links
now, look on the left side and click on the blue triangle, the field will expand and show a blue triangle next to the line that says "previous versions"
the proper way to flash is to READ THE INCLUDED FLASH DIRECTIONS THAT ARE INCLUDED WITH THE BIOS FILE
FOR OS'S NEWER THAN WINDOWS 7, do not use the windows flasher, use the usb key or bios update method, both of these methods require you to extract the bios file by running the "sp75724.exe" or if using winzip right click and select extract and then cancelling the windows update prompt
now go to the extracted folder on c:\sp75724.exe and go into the DOS folder and copy all of the files onto a fat 32 bootable usb key (boot from key flash) and run "flashbib"
or (my preferred method) place the 7G5_0360.bin file on a formatted fat32 usb key, insert into a z800 usb port, power on the system enter the bios and select "update bios " it should find the key and see the bios file, follow prompts and it will load the new bios and perform the flash
for more help read the included README file in the DOS folder
i have attached the extracted DOS folder of the latest (last z800 bios)
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