BIOS & ROM on the Motherboard

[Franky]

Hi guys,

I'm going to find the following info about new/recent computers. Is there anyone who likes to help?

1-Where the BIOS is stored on the motherboard? Inside the ROM, EPROM or something like USB storage on the motherboard?

2- I have also heard that this (BIOS) is stored into CMOS and a battery supplies the power for the settings of the BIOS, correct?

3- Also I have read that in the new motherboards there is a jumper that can delete the settings of the BIOS. What's your thoughts?

Thanks in advance.

 

[3D Jed]

The BIOS is a chip on the mobo. There are some hard wired default settings, and volatile user settings. The 1st time a mobo starts, the user settings are the default settings. If you change anything eg boot order, or overclock the cpu etc and click save (often F10) the new settings are used (not the default). The user data is kept alive by a battery. If the battery fails, the BIOS returns to default. Taking out the battery is one way to reset the BIOS to default. Another way is to temporarily connect a mobo jumper to clear the BIOS, or go into the BIOS screens and choose default settings.

When changing BIOS settings for overclocking, it's easy to screw things up so the pc won't even boot - solution is to pop the battery out for a couple of minutes to reset back to default.

HTH

 

[Franky]

BIOS is a code. What is it stored into? In a specific chip/storage?
Is there any ROM/EPROM/EEPROM on the motherboards nowadays?

 

[derekimo]

HowStuffWorks "How BIOS Works"

Where is the BIOS Stored?

 

[Britton30]

BIOS is on ROM chips nowadays, in the past were used EPROM, and EEPROMS. Many newer mobos have a removable BIOS chip. Like this:

EDIT: Part of the ROM is in fact EPROM and EEPROM to let us change settings.
I was thinking of the old chips where they were flashed...with a bright light or ultra-violet.

Others are still hard soldered to the mobo like this:

 

[UsernameIssues]

BIOS is on ROM chips nowadays, in the past were used EPROM, and EEPROMS. Many newer mobos have a removable BIOS chip.
~~~

Then by definition (Read Only Memory), you could not update it without changing the chip. But you are correct, the flash memory used for modern BIOS storage is often called ROM. I just think it is a poor choice of terms.

 

[UsernameIssues]

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2- I have also heard that this (BIOS) is stored into CMOS...
~~~

CMOS is a type of semiconductor used to make - well - semiconductors (chips). The name/type/function of the chip could be EEPROM. But BIOS used to be stored in two different chips. The chip that is used for the Real Time Clock (RTC - which needs a battery) often times used CMOS semiconductors. Some BIOS info was stored in that chip too. The industry never seemed to pick a name for the chip that dealt with the RTC; so, it was just called CMOS. From what I've read, vendors are moving away from the scheme of splitting BIOS info between two different chips.

~~~
...and a battery supplies the power for the settings of the BIOS, correct?
~~~

The battery is needed when there is no other power source (e.g. power from a wall socket/outlet). If all BIOS info is stored in non-volatile memory (like flash memory) then the battery is not needed for BIOS... only for RTC.

 

[Franky]

Thank you guys for your info. When I read those posts all at one time and sequentially, I confused somewhat. I think I need to reread them more than one time!

 

[UsernameIssues]

Thank you guys for your info. When I read those posts all at one time and sequentially, I confused somewhat. I think I need to reread them more than one time!

I have that effect on people

 

[Franky]

LOL. But why?

 

[UsernameIssues]

I have to be careful to use terms that most will understand.

Hopefully, my posts were not too confusing.

 

[Britton30]

Yeah it is confusing, but this post by Derek is the clearest I think.