This information was found at www.csd.toshiba.com
You can access the BIOS settings on these models using any one of these 3 methods.

1. From the Windows Control Panel, launch the Toshiba HWSetup program. HWSetup provides a user-friendly graphical frontend for modifying BIOS settings. Please note that if you change some settings, you may be required to restart your computer. HWSetup comes preinstalled on your Toshiba portable PC, or it can be downloaded as part of the Toshiba Utilities package for your model.

2. Press the [Esc] key while the system processes its Power On Self Test (POST). In order to use this method, the computer must be "off", meaning not in sleep/suspend or hibernate mode. Press the power button, then immediately press the [Esc] key (it doesn't hurt to hold the key down). When the POST finishes, you'll be prompted to press the F1 key to enter BIOS setup. Press the [F1] key to access the BIOS setup program.

3. From MS-DOS, run the TSETUP program. TSETUP must be run under real mode DOS (not a Windows-based MS-DOS prompt) with no memory manager (like HIMEM.SYS, QEMM386, or equivalent) installed. TSETUP was provided originally with your computer, or you can download it from this Website