At 12:23 PM 2/12/99 , you wrote:
>Hello there
>
>Could someone please tell me the difference between BIOS & CMOS. I have read
>various explanations but they kinda merge to me!!
>A simple definition will be appreciated.


Basically:  the Bios is the onboard chip with hard coded instructions that allows
the motherboard to recognize and work with other devices AND the CMOS is
the settings you can change in the Bios for those devices.

This is the more elaborate defination  on our web site found at:
        http://nospin.com/pc/pcb05.html#bios
===================================================
                  BIOS (Basic Input/Output System)

BIOS is the program a personal computer's microprocessor uses to get
the computer system started after you turn it on. It also manages data
flow between the computer's operating system and attached devices
such as the hard disk, video card, keyboard, mouse, and printer.

BIOS is an integral part of your computer and comes with it when
you bring it home. (In contrast, the operating system can either be
preinstalled by the manufacturer or vendor or installed by the user.)
BIOS is a program that's made accessible to the microprocessor on
an eraseable programmable read-only memory (EPROM) chip. When
you turn on your computer, the microprocessor passes  control to the
BIOS program, which is always located at the same place on EPROM.

When BIOS boots up (starts up) your computer, it first determines
whether all of the attachments are in place and operational and then
it loads the operating system (or key parts of it) into your computer's
random access memory RAM from your hard disk or diskette drive.

With BIOS, your operating system and its applications are freed from
having to understand exact details (such as hardware addresses) about
the attached input/output devices.  When device details change, only the
BIOS program needs to be changed. Sometimes this change can be
made during your system setup. In any case, neither your operating
system or any applications you use need to be changed.

Although BIOS is theoretically always the intermediary between the
microprocessor and I/O device control information and data flow, in
some cases, BIOS can arrange for data to flow directly to memory
from devices (such as video cards) that require faster data flow to be
effective.

            CMOS (complementary metal-oxide semiconductor)

CMOS is the semiconductor technology used in the transistors that are
manufactured into most of today's computer microchips. Semiconductors
are made of silicon and germanium, materials which "sort of" conduct
electricity, but not enthusiastically.  Areas of these materials that are
"doped" by adding impurities become full-scale conductors of either extra
electrons with a negative charge (N-type transistors) or of positive charge
carriers (P-type transistors).   In CMOS technology, both kinds of transistors
are used in a complementary way to form a current gate that forms an
effective means of electrical control. CMOS transistors use almost no power
when not needed. As the current direction changes more rapidly, however,
the transistors become hot. This characteristic tends to limit the speed at
which microprocessors can operate.

Typically, the area of the BIOS that is configurable for the system user,
that allows the system to recognize seperate components is referred to
as the CMOS or CMOS settings.

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