An updated bios doesn't really help with that problem. How discs are read depend on the drive, the media, the source, how it is burnt etc...
For updating...
Burn the bios to disc, or copy it to your hard drive
Go to the X3 Bios, and go to Bios Tools, Flash Main Bios...
There are options to load bios from C:, E:, F: or From DVD-ROM
Or you can reflash your bios using FlashBios again...