First go here.
http://www.howtogeek.com/136987/how-to-create-a-bootable-dos-usb-drive/
Now go here.
http://www.dell.com/support/drivers/us/en/19/DriverDetails/Product/xps-420?driverId=R215689&osCode=BIOSA&fileId=2731125974&languageCode=EN&categoryId=BI
Follow the directions.
i have a dell xps 420 and i am looking for a bootable version of the bios anyone got any ideas??

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