I forgot bios password on toshiba equium l20-197 how can i reset or enter the bios thanks

  Inorder to reset the password, you must open the case,  and on the Motherboard there is a round battery. Its the size of a nickel.  In some cases you can just remove the battery and wait a few seconds and then replace it.
  Another alternative is to short some pins that will clear the bios password.  In close proximity to that battery you should find a set of pins. Normally there are 3 pins together and there will be a jumper on one end of the 3 pins. What you have to do is to remove the jumper and move it to the other end of the pins. In other words if the pins are labeled 1-2-3 and right now there is jumper on 2 and 3., Then you will remove the jumper from there and place it on pins 1 and 2.    Once doing so will reset the password on the bios.  Wait a minute and then replace the jumper on 2 and 3. And then you should have your problem resolved....
                                                 Joe  < Data Miner >