BIOS error

Compaq LTE 3500 laptop, Win98, startup error, Wont start on hard disk, or on floppy disk with or without hard drive connected. At startup gives F10 prompt for BIOS but wont open BIOS, then goes straight to “81920” error code, then “Password verification” box “Enter password” OK and freezes. I have repeated this after the CMOS battery removed overnight. The BIOS needs to be reprogramed, but how?