BIOS CMOS Explain please!

PD75

Are they the same thing or not? I looked at the technotes but im still confused.
Thanks for your help

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Comments

garv221

CMOS is what keeps time & settings through a battery for BIOS & BIOS is what configs and loads your start up options--Boot, CPU speed, system password and so on. Clear your CMOS and you re-set your BIOS

PD75

So BIOS is used to change settings on hardware. ie IRQs?

And CMOS has no other role excpet date/time?

lazyart

CMOS holds the settings that you change in BIOS Setup.

http://www.techexams.net/forums/viewtopic.php?t=5146

PD75

So when you add new RAM or a new CPU you have to flash the BIOS so that your system will take on baord the new FRU's?

CMOS is where you tell the system you are adding the new FRU's?

lazyart

Um, no.

Go into your system's setup by pressing DEL or F1 when you power up... it varies a bit by manufacturer-- read the screen before windows starts.

From there you will see the options. DON'T GO CHANGING THEM unless you know what you are doing. Systems today don't need to be told that memory or CPU has been changed-- they can figure it out on their own and adjust-- but this wasn't necessarily the case 6-7 years ago.

PD75

"
CMOS holds the settings that you change in BIOS Setup."

Sorry layart if im doing your head in mate.

So when you hit F1 you get the screen right. This is CMOS?
Where is the BIOS set-up?

PD75

Whe you press F1 you get a blue screen. Is this the CMOS setup? It has things like Standard CMOS setup, PNP, PCI, Onboard I/O, Password setting, Load BIOS Default , etc.

What then is the BIOS?

garv221

What are you working on a 67' Acer?

BulletToothTony

In all honesty, I wouldn't focus too much time on the BIOS/CMOS for your test. You are going to be hit with some many other questions, that you are going to regret focusing on this one matter. Aside from tech notes, what else are you using for your exam? The exam cram book is Marc Minassi books are great and have really good explanations.

mwgood

http://www.learnthat.com/courses/computer/comptia/aplus/comptia02/comptia02-12.html

lazyart

paul1975 wrote:

Whe you press F1 you get a blue screen. Is this the CMOS setup? It has things like Standard CMOS setup, PNP, PCI, Onboard I/O, Password setting, Load BIOS Default , etc.

What then is the BIOS?

You are in your system setup. These settings are stored in CMOS and used by BIOS. You won't need to know the settings and such, but understand the relationship.

BIOS starts the computer up (and you thought it was the power button) and hands control over to the OS. BIOS uses the settings stored in CMOS that you are looking at in the setup screen. Stuff like drive types, memory timings, and even processor speeds can be stored here (processors are auto detect, but many systems let you set it manually).

You could be asked where do you set up your disk drive parameters (Cylinders, Heads, Sectors) and boot sequence. That is setup. Where are the settings stored? CMOS. You can flash the BIOS code to take advantage of some features and compatibility fixes. You'll want to reset CMOS when you do or you could have a mess.

This was certainly one chapter I skipped over in my studies. What's fun is that setup, cmos and BIOS are often used interchangeably to describe Setup itself... but they are three seperate but related entities.