there is also a way to do it on laptops it just involves making your own jumper out of cooper wiring. i know of a friend who recently did this its a bit more trick but also doable im sure there are videos on youtube
This is a fact. My very first computer, an incredibly made Toshiba Satellite Pro 420 lappy (I still have it in a closet, I would never throw it away), I took out after it was stored for 5 years and realized could not remember my bios PW!
I read about the above online, could not manage the rewiring myself, but found a pre made one on ebay! It was $15. I had big emotional attachment to the machine, so I got it. It worked.
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Edit: I just delved and found the instructions:
http://hackaday.com/2011/03/08/laptop-bios-password-recovery-using-a-simple-dongle/
But I doubt this would be an option on a laptop much newer than my beloved Toshiba, cause parallel ports went away when USB took over.
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Edit: Just found this, unless there is some reason you can't verify ownership, I would follow up ASAP and call Dell.
There's no clear CMOS jumper. If you forget the password, call Dell - upon verification of ownership, they will issue a system-specific master password for you to use to clear the password. The password is not stored in CMOS memory - it is stored in nonvolatile, flash EEPROM memory.