Http://cgi.ebay.com/ws/eBayISAPI.dll?VISuperSize&item=200434969029
Black chip, upper left of motherboard in this photo
If you are trying to clear a BIOS password, you'll either need to contact Dell or replace the chip, as it cannot be cleared manually.
http://www.fixya.com/support/r3656360-dell_portable_computer_bios_hard_drive