Fiddling with motherboards and trying to reset eproms and chips is a hazardous business at the best of times. OK - if there is no other way then that is all you can do, BUT ..... if you can prove ownership of the PC and it is still supported (which you can check on the DELL website), whether it be a laptop or a desktop, then DELL technical support can actually help! You need to have the PC TAG and the character sequence from the boot time/BIOS entry failure message, and then contact the local DELL TS. They can then email an unlock code which has to be typed in. I have done this many times at work, where users have left and their machines are unusable until unlocked.