If your laptop still has its original factory software, use the application.
A few questions before I proceed:
The most common way to update is through the Windows-based utility provided by Dynabook Support (formerly Toshiba). Toshiba Satellite C50-A BIOS 1.70 - Softpedia Drivers 23 May 2014 — * BIOS. Motherboard. Toshiba Satellite Pro C50-A BIOS 1.40 - Softpedia Drivers toshiba satellite c50a bios update