If you flash a new BIOS and it fails it will be difficult to revert to the old one. Hopefully you have a PCI video card around so you can boot with both the card that needs flashing and a working one.
Since it's not a Connect3D X800GTO or Sapphire X800GTO2 then I would say it's not going to flash to an X850 series and as a result you should stick with your current BIOS and just use ATITool to overclock.
if the red F's are F's in your fuse list also then you will probably be able to go X850. Just make sure to test the overclock speeds before you go flashing, for example the X850XT-PE is 540/590 so if your mem cannot do 590 then do NOT flash that BIOS, even if your card is unlockable.