PCG-FX, PCG-F, PCG-FXA
If you attempt to update the BIOS in your system and have installed additional RAM in slot #2 you have a good chance of a bad BIOS flash occurring.
ALL RAM installed in slot #2 (toward front of the system) should be removed prior to flashing the BIOS.
Sony incorporates the Keyboard Controller firmware into the BIOS image available for download. When the failure occurs is during the updating of the KBC image in the last portion of the update process.
Not only can you end up with corrupt BIOS information rendering your notebook dead but also various power component failure, including the KBC chip.