PC Hardware Sivaji Academy

How to reset CMOS?How to Clear CMOS?How to Reset BIOS?Where is CMOS reset Jumper?


  • The computer BIOS settings are stored in a Memory IC which is called as CMOS.
  • This memory IC remembers the data ( i.e. the basic configuration) because of a small button type  battery cell placed in the mother board. 
  • Put off the Power supply. Remove the small button like battery in the Motherboard  and replace it againThe cmos configuration will be reset to default configuration.
  • Another method: Put of the power supply. Remove the Jumper labelled  CLEAR_CMOS. ( jumper means a small pin of U shape) and replace it after one minute. 
  • CMOS stands for Complementary Metal Oxide Semiconductor. This Memory is basically RAM (Read and write memory) which means it will loose its contents if its power is disconnected. That is why  the battery cell is always connected to this RAM. Because of this arrangement, the memory does not volatile. Hence this IC is called as NVRAM(Non Volatile RAM)
  • BIOS stands for Basic Input Output System