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BIOS Settings

Drives, Boot Order and Clearing the CMOS


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Boot Order

This is the most important setting for when you first build your computer. The boot order determines which devices the motherboard will look at for an operating system or installer. The options typically include Hard Drive, Optical Drive, USB and Network. The standard order at first startup is Hard Drive, Optical Drive and USB. This will generally cause the system to find the hard drive first which will not have a functional operating system if it has just been installed and is blank.

The proper sequence for the installation of a new operating system should be Optical Drive, Hard Drive and USB. This allows the computer to boot from the OS installation disc that has a bootable installer program on it. Once the hard drive has been formatted and the OS installed, it is important to then restore the boot order of the computer to the original of Hard Drive, DVD and USB. It can be left with the optical drive first but this will often cause an error message of no boot image found which can be bypassed by pressing any key on the system to then search the hard drive.

Drive Settings

With the advances made by the SATA interface, there is little that needs to be done by users in terms of drive settings. Generally drive settings are typically only adjusted when you are planning to use multiple drives in a RAID array or using it for Intel Smart Response caching with a small solid state drive.

RAID setups can get quite tricky as you generally need to configure the BIOS to use the RAID mode. That is the simple part of the setup. After that is done, you will need to create the array of drives using the BIOS from the hard drive controller specific to the motherboard or computer system. Please consult the instructions for the controller on how to enter the RAID BIOS settings to then configure the drives for proper use.

Problems and Resetting the CMOS

On some rare occasions, the computer system may not properly POST or boot. When this occurs, typically a series of beeps will be generated by the motherboard to indicate a diagnostic code or an error message may even display on the screen with more modern UEFI based systems. Pay close attention to the number and types of beeps and then refer to the motherboard manuals for what the codes mean. Generally when this occurs, it will be necessary to reset the BIOS by clearing the CMOS that stores the BIOS settings.

The actual procedure for clearing the CMOS is fairly straightforward, but check with the manual for the steps to double check. The first thing to do is power off the computer and unplug it. Let to computer rest for about 30 seconds. At this point, you need to find the reset jumper or switch on the motherboard. This jumper is moved from the non-reset to reset position for a brief moment and returned back to its original position. Plug the power cord back in and reboot the computer. At this point, it should boot with the BIOS defaults allowing the settings to be redone.

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