Learning Objectives

Other features

• BIOS program continually checks the CPU temperature and voltages, the cooling fans RPM, etc.
• If over heating occurs, the PC will shut down automatically.
• The PC can also be turned on by for example modem signals, since the power supply is controlled by the motherboard.
• The on/off button will turn the PC "down" without turning it completely off.

tattoo

• Some BIOSes contain a "tattoo", a digital signature placed inside the BIOS by the manufacturer, for example Dell.
• Computer manufacturers that distribute original equipment manufactured (OEM) versions of Microsoft Windows and Microsoft application software can use the tattoo to authenticate licensing to the OEM Windows Installation disk and/or system recovery disc containing Windows software.
• Dell systems having tattoos do not require entry of the Product Key (the Product Key on the label in fact being invalid), and they bypass Windows Product Activation (a convenience to the user and to Microsoft).

Non-IBM compatible PC

• Apple Macintosh, where the system software originally relied heavily on the ToolBox—a set of drivers and other useful routines stored in ROM based on Motorola's 680x0 CPUs.
• These Apple ROMs were replaced by Open Firmware in the PowerPC Macintosh, then EFI (Extensible Firmware Interface) in Intel Macintosh computers.

Why upgrade BIOS

• Large hard drive support. Older BIOS's couldn't see drives larger than 37GB due the 48bit problem.
• New video card technology such as AGP 8X support, or in older machines 2X to 4X. This includes SLI.
• Advanced Configuration and Power Interface (ACPI ) compatibility
• CPU support. BIOS companies often release new CPU microcode updates to the motherboard companies who in turn add them to their BIOS's to support newer CPU's
• Fix problems. A common problem is USB compatibility. There are so many USB devices nowadays and many of them try to use the same interrupt request (IRQ). Hence, as the system BIOS is loading, IRQ conflicts can cause USB devices to not be found.
• Memory support. Newer faster memory can have issues on your motherboard. Might be larger than what was originally tested or approved. A tweak from the motherboard company can fix that.