Hi Survesuwaran, By doing a Reset or Refresh, the computer will be restored to the factory settings so that drivers will be installed so does the OEM information. Same thing will happen if you restore the computer using the Recovery CD's. Please ensure to back up data before performing either of these.
i have inspiron 14r 5420 (with windows 8 ) . i have problems with the laptop after a few days and earlier i had did recover media to 2 CDs.  Now during the boot it was verifying my laptop and it say that it would reset the pc to factory backup. Will this process require a format.
Dell backup and recovery - system recovery