You can try this, I did it and it worked. You must be conversant with hardware to do this.i have two option of which I have tried one.
Open you computer and try to locate where the BIOS Jumper is located, then remove it boot the machine without the jumper and the shut-it down, insert the jumper and boot again you will be able to access you BIOS setting without it requesting a password. Personally I haven't tried this.
Remove the battery for some minutes (lets say 5 minutes) to drain out the power in the machine then power-on the machine but connect it to a source of power, don't insert the battery.If it doesn't work try this one out, I am very optimist it will because I have tried it myself.
Open the computer and try to locate where the CMOS Battery is (it looks like a very big watch battery), remove battery and then switch or power-on the machine without the battery. Then shut-down the machine and insert the battery (should be very careful in both removing and inserting the battery), then power on the machine this time if you decide to go to BIOS setup,. it wont ask for the password.
But I think you'll have to set the time/date in your BIOS.
English SOLUTION: open the computer, look for a 3 wire jumper called JCMOS, see that the jumper is located in 2 of the wires, take the jumper off and change the location of the jumper to the first wire and the middle one, then take it off again and put it like it was at the begining, that's it! Bios pass it's gone!
bought dell e6400 online unfortunatley it was pass worded thinking of selling it for parts but doubt i,ll get back what I paid for it ,need. some freindly advice ,tried cmos removal for 3 months sick of looking at it at this stage .is their any thing I can do with it seemed to be a shame to break it for parts as its very new looking thanx