Bios Mods -The Best BIOS Update and Modification Source

i would like to have an option that switch off nvidia optimus and used nvidia graphic card instead or integrated intel graphic card.

link for the bios = http://www.dell.com/support/drivers/us/e...Id=R309835

Its a UEFI bios and all UEFI ( secure core tiano ) can`t be unlocked now and are under development .
Thank you ,
Ahmed

I updated my BIOS from A05 to A10. Now the system does not restart or shutdown anywhere ( in Windows, Ubuntu, Mac OS x and even in BIOS setup ). Hence I cant use Winflash in windows as it needs a restart to flash the bios.
so where can I find the Phoenix UEFI flash utility for DOS or commands for winflash to flash the bios without reboot?