CMOS Setup

CMOS setup is a little intimidating the first couple of times you work at it.  The important thing here is patience.  All BIOS screens seem to change all of the time.  Just don't mess with voltages or increase anything called a multiplier.  Other than that, have at it, the tip in the yellow box below will show you how to bail yourself out if you get into trouble.

The key items for CMOS setup are

  • Boot order - This will let the computer know which device to look for to find the boot record.  (Where Windows is)
  • Feature enabling - You may have to enable things like front USB, or in the case below enabling RAID modes from the SATA drives.  The default was off.
  • Confirm CPU settings - Almost all of the time this is correct, when the computer boots up, as long as it gives you the correct indication of CPU  in the first screen show below, your settings will be fine.
  • RAM settings - More and more often it seems these are wrong.  The good news is it's really easy to change as all of the information will be with your RAM sticks.  If you match the MHz, voltage and timings on the package you'll be good to go.  If you enter a wrong timing, most settings will reset on a reboot, use the tip below if your computer stops booting.
  • Time - You can change this in the BIOS, but lately since Windows will correct it, I just do it there.  Changing with page up keys and arrows bites, I take the easy road.
That's really it, play with any settings you're curious about first, that way you can easily default back.  I've never seen 2 identical BIOS screens, and it rarely takes me more than 5 min to go through everything.  Just take your time, refer to your motherboard documentation and you'll be successful.

CMOS Setup Step by Step

TIP! As long as you're not messing with voltage, you can pretty much do whatever you like, if the computer then fails to boot, remove the CMOS battery and pull the power cord to reset the CMOS and start over.

  • Step 1 - The default to get in on most is by pressing the delete key right at the start of boot up.
enter cmos
  • Step 2 - Load setup defaults.
bios load setup default
  • Step 3 - Enter the current Date and Time.
bios main screen
  • Step 4 - Change the boot sequence.  This is simply the order the computer will look for an operating system to boot.  I usually go CDRom, then floppy, if I have one installed, then the Hard Drive.
bios boot sequence
  • Step 5 - Check your CPU settings.  The default ones should be correct, if they are not adjust the CPU to manufacturers specifications.
bios cpu settings
  • Step 6 - Check the settings of your RAM.  Often the settings are actually on your RAM, if not check the manufacturers website.  Even some RAM voltages are different these days so this step is important.
cmos ddr
  • Step 7 - Adjust your plug and play settings, just change plug and play O/S to yes.
bios pnp
  • Step 8 - Enable the controller if you plan on using any USB devices, enable 2.0 support and legacy support to make sure all your USB devices work at their maximum.
bios usb
  • Step 9 - If you are planning on using a Raid, make sure you enable to option for those drives.
bios raid config
  • Step 10 - If your motherboard supports it, and you would like your computer to be as silent as possible, enable quiet fans.  This will slow down your computer fans when the cooling is not needed.
bios fan control
  • Step 11 - Save your changes and exit.
bios save

If you see other settings you would like to know more about, google the exact name as you see it in CMOS setup.

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Updated October 14 2013

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