you can still get into BIOS in Dell computers, just not through the del key in all cases, HPs for example use F1 if I am not mistaken. At my school though, the Dells can acess BIOS through del. again as everyone else said, you cannot OC most store bought PCs
you dont turn on the BIOS <_< , you just enter it and if you have a DELL, you can enter the BIOS, you just cant overclock it, those options are locked.
Read next time please and stop wasting our time here in computing, He has a dell therefore=no overclock.