What is a BIOS and UEFI?
BIOS setup program is used to customize the particular aspects of the computer hardware so that it can fit the requirements of users. The manufacturer of the BIOS determines which feature of the hardware can be customized by the user. Incorrect setting can have adverse effect so the user should have clear understanding about the effects of the changes.
The following are features that can be customized and configured in Bloc setup:
Time and date: In the main page of BIOS setup utility, there are two fields: System Time and System Date,. These two fields are used for setting the system clock. The OS and the other programs refer these two fields to set the time and date. So, these two fields should be set correctly otherwise the OS and the other programs will display incorrect date and time. Apart from that the maintenance program will interpret that the system is outdated and will seek to update the programs and files constantly. Also, the calendar program will not be able to display the reminder on correct time or date.
Enabling and disabling devices: Advanced BIOS setting can be setting enable or disable the devices that are required and not required by y computer. For example, the motherboard of a computer system have a built-in device which has networking capabilities. But if a user installs an adapter card for performing networking capabilities, it may cause redundancy with the built-in device. So, in such case disabling the device becomes necessary. In the same way, many hardware devices as serial and parallel port, FireWire port, and infrared hardware may be disabled or enabled as per the requirement. If any device does not work it becomes necessary to check the advanced BIOS setting to see whether the device is disabled or not, and if it is disabled. whether it is disabled by default or someone has disabled it. When the device is enabled in the BIOS setting, it can be used by the computer.
Boot sequence: Boot sequence, also called as boot order, is actually an ordered list of devices that the computer is allowed to boot from the OS. This list is generally shown under the Boot tab of BIOS setup utility. Apart from the hard drive, user can also boot optical drives, floppy drives, flash drives, etc. that are listed in the BIOS setup as boot sequence options. To do boot sequence for any device, it is required to enable that option in the BIOS setup utility. You can also disable or remove a device from the boot ordered list.
Clock speed: The CPU clock speed can also be changed by BIOS setup programs. However, if you reduce the speed of CPU clock it will make your computer run slower but it will make your device ice cooler. There will be less noise of fan in the computer system. But if you increase the clock speed, your computer will run faster and the fan noise will increase as well. It may also increase your CPU’s temperature. Increasing the clock speed more than the manufacturer’s recommendation is called as overclocking. Overclocking is never recommended as it is a risky task and it voids the warranty period of the CPU. Moreover, overclocking can damage the CPU or can shorter the lifespan of CPU. Even if it is required to overclock the CPU it is highly recommended that you install a cooling system that has the capability of dissipating the extra heat that will be generated due to overclocking.
Virtualization support: If a computer has virtualization support, it will allow the user to run multiple OS in separate files and partitions. For accomplishing the virtualization technology, it is required to enable the virtualization setting in the BIOS setup utility of the computer. If you do not need the technology of virtualization, you should disable the virtualization setting in the BIOS setup utility.
Security: Various types of security features are supported by BIOS to protect the BIOS setting and data on the hard drive, and also in recovering the computer system in case it is stolen. Some common security features that can be found in BIOS are:
BIOS password: BIOS password is used so that various levels of access can be granted to the BIOS setting. Generally, there are two types of passwords: supervisor password and user password. Supervisor passwords are special type of passwords, which can access user-access password and all BIOS setting and screen. But the user-access passwords are used to define the level of access that can be granted to the users. This type of password can become available only after the supervisor password is enabled.
Some common levels of access that can be granted to the user are full access, limited access, view only, and no access. In full access, the user can view all available screen and settings except the supervisor password setting. In limited access, user can only make changes to a specific setting, such as changing the date and time. In view only access, user can view all the screens but they will not be allowed to change any settings. In no access the user will not be allowed to access any BIOS setup utility.
Drive encryption: In this type of security, the hard drive is encrypted so that it can be prevented from data theft. In this process, the data are changed into codes which cannot be understood. The data which are encrypted remain encrypted even if someone places the hard drive in another computer. It will require the correct password to boot up the computer system and to decrypt the data.
Trusted Platform Module (TPM): TPM is a specialized kind of chip where the security items, such as encryption keys and passwords are kept. It contains endorsement key (EK) which remains inside the chip. It cannot be accessed even by any kind of software.
Lojack: It has two parts which are used to protect the computer system from absolute software. These two parts are persistence module and application agent. The manufacturer of the computer system installs the persistence module in the BIOS at the time of manufacturing, whereas user generally installs the application agent. The persistence module is activated only when the application agent is installed by the user. After the persistence module is activated, it cannot be turned off. In case someone removes the application agent from the computer, the persistent module can install it again. The application agent is so powerful that it can report device information and location of the computer system by calling absolute monitoring centre over the Internet. This is very useful if the computer system is lost. With the absolute software, the owner of the computer system can lock the computer system remotely; delete sensitive data remotely that are stored on the computer; locate the computer with the help of geo-technology; etc.