It's because toshiba satellite computers are made in japan and are cruddy products. mine does the same and now i cant even get the screen to remain on fore more than 2 seconds. toshiba has a stupid answer for this problem on their website which does not fix the hardware problem with the screen.
Elisha, July 2005
edit
I can answer this question...
why do i have a blank screen after flashing the bios?