Flash memory in motherboards?

[[email protected]]

So... when can we expect motherboards to use Flash memory (instead of
battery-powered NVRAM) to store BIOS settings for our motherboards?

Those coin lithium batteries are... old-fashioned.

Even the newer Asus boards seem to have a lithium battery for storing
BIOS settings...

http://usa.asus.com/products4.aspx?modelmenu=2&model=185&l1=3&l2=12&l3=34

(press Don't Install if it asks to update your Macromedia.)

Michael

 

[Spehro Pefhany]

So... when can we expect motherboards to use Flash memory (instead of
battery-powered NVRAM) to store BIOS settings for our motherboards?

Those coin lithium batteries are... old-fashioned.

Even the newer Asus boards seem to have a lithium battery for storing
BIOS settings...

http://usa.asus.com/products4.aspx?modelmenu=2&model=185&l1=3&l2=12&l3=34

(press Don't Install if it asks to update your Macromedia.)

Michael

That would be a waste of money (something MB manufactuers are loathe
to do). The battery is needed anyway for the RTC. Keeping an
additional chunk of RAM alive is virtually free. What do you suggest,
an expensive double-layer capacitor? Flash would also be less
approprate than EEPROM technology.


Best regards,
Spehro Pefhany

 

[[email protected]]

That would be a waste of money (something MB manufactuers are loathe
to do). The battery is needed anyway for the RTC. Keeping an
additional chunk of RAM alive is virtually free. What do you suggest,
an expensive double-layer capacitor? Flash would also be less
approprate than EEPROM technology.


Best regards,
Spehro Pefhany

I thought EEPROM was more expensive than Flash. Oh well... my
information must be out of date.
http://www.netrino.com/Publications/Glossary/MemoryTypes.html

Thanks for the reminder re: the RTC...

 

[Spehro Pefhany]

I thought EEPROM was more expensive than Flash. Oh well... my
information must be out of date.
http://www.netrino.com/Publications/Glossary/MemoryTypes.html

Not out of date. It *is* cheaper for *large* memory sizes, but...

1] In your reference above, see the "sector erase" issue with flash.
EEPROM can be changed one byte at a time.

2] The amount of memory required for BIOS *settings* (as opposed to
the BIOS *program*) is quite small. Early ones were 64 bytes with the
first 16 used for the RTC. Newer ones are probably several times that
size, but still tiny compared to even a small flash memory. The
smallest flash memory out of the 2200+ different types that Digikey
carries is 256K bits (there's one shown erroneously as 1K, but it's
actually 1M). They go up to a rather staggering 8G bits. EEPROMs,
OTOH, start at 128 bits (16 bytes) and go up to about 1M bits. So, not
only do you have the sector erase issue, but most of the memory would
be wasted.

Of course some settings *are* stored in flash, in a sense, since the
factory default settings are part of the BIOS program, which is
generally stored in flash these days. One could write a BIOS to store
the settings in the large program flash, if it has the ability to
boostrap, but that could result in a dead motherboard and an angry
customer if the power failed or a crash occured during the routine
writing of values, so I think most engineers will not be overly eager
to invite that kind of problem to the door. Even if it happens only
rarely, it's an extremely serious problem to the user.


Best regards,
Spehro Pefhany

 

[Pooh Bear]

I thought EEPROM was more expensive than Flash. Oh well... my
information must be out of date.
http://www.netrino.com/Publications/Glossary/MemoryTypes.html

Not out of date. It *is* cheaper for *large* memory sizes, but...

1] In your reference above, see the "sector erase" issue with flash.
EEPROM can be changed one byte at a time.

2] The amount of memory required for BIOS *settings* (as opposed to
the BIOS *program*) is quite small. Early ones were 64 bytes with the
first 16 used for the RTC. Newer ones are probably several times that
size, but still tiny compared to even a small flash memory. The
smallest flash memory out of the 2200+ different types that Digikey
carries is 256K bits (there's one shown erroneously as 1K, but it's
actually 1M). They go up to a rather staggering 8G bits. EEPROMs,
OTOH, start at 128 bits (16 bytes) and go up to about 1M bits. So, not
only do you have the sector erase issue, but most of the memory would
be wasted.

Of course some settings *are* stored in flash, in a sense, since the
factory default settings are part of the BIOS program, which is
generally stored in flash these days. One could write a BIOS to store
the settings in the large program flash, if it has the ability to
boostrap, but that could result in a dead motherboard and an angry
customer if the power failed or a crash occured during the routine
writing of values, so I think most engineers will not be overly eager
to invite that kind of problem to the door. Even if it happens only
rarely, it's an extremely serious problem to the user.

Not to mention that you would lose the 'discharge CMOS' option with a jumper !
An invaluable aid.

Graham

 

[Adrian Jansen]

That would be a waste of money (something MB manufactuers are loathe
to do). The battery is needed anyway for the RTC. Keeping an
additional chunk of RAM alive is virtually free. What do you suggest,
an expensive double-layer capacitor? Flash would also be less
approprate than EEPROM technology.


Best regards,
Spehro Pefhany

One could argue that even the RTC is almost not needed in most desktop
PCs now, they could get the time direct off the Net. Then you do have
some savings - no pesky battery, and no CMOS ram.


--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Design Engineer J & K Micro Systems
Microcomputer solutions for industrial control
Note reply address is invalid, convert address above to machine form.

 

[Pooh Bear]

One could argue that even the RTC is almost not needed in most desktop
PCs now, they could get the time direct off the Net.

You're assuming everyone's connected to the 'net' !

Graham

 

[Spehro Pefhany]

One could argue that even the RTC is almost not needed in most desktop
PCs now, they could get the time direct off the Net. Then you do have
some savings - no pesky battery, and no CMOS ram.

I expect functionally PC-like thingies (perhaps thin clients on
wireless mesh networks) may well go that way.


Best regards,
Spehro Pefhany

 

[Deefoo]

only do you have the sector erase issue, but most of the memory would
be wasted.

As if anyone cares about wasted memory in the PC world.

--DF

 

[Spehro Pefhany]

As if anyone cares about wasted memory in the PC world.

--DF

I have not noticed any video cards which use 1G of memory where a mere
64M would do.


Best regards,
Spehro Pefhany

 

[Deefoo]

I have not noticed any video cards which use 1G of memory where a mere
64M would do.

And you think that all those 64M bytes are being used? Hardware guys put on
enough memory so software guys have plenty to waste.

--DF

 

[Michael]

So... when can we expect motherboards to use Flash memory (instead of
battery-powered NVRAM) to store BIOS settings for our motherboards?

Those coin lithium batteries are... old-fashioned.

Even the newer Asus boards seem to have a lithium battery for storing
BIOS settings...

http://usa.asus.com/products4.aspx?modelmenu=2&model=185&l1=3&l2=12&l3=34

(press Don't Install if it asks to update your Macromedia.)

Michael

If you object to the coin cell, remove it and wire in a series pair of AA cells
(assuming the coin is 3v, of course). The last time I did this mod was in 1999,
to an IBM PC-AT. BIOS was still fine yesterday when I used that machine to
assemble some MC68705 code.

 

[Michael]

You're assuming everyone's connected to the 'net' !

Graham

Agreed. Heartily! That breed of assumption is too common, causes no end of
frustration/problems.
Of the half dozen PC's I use, only one ever connects to the web.

 

[Keith]

And you think that all those 64M bytes are being used? Hardware guys put on
enough memory so software guys have plenty to waste.

64MB isn't much these days either. Even this laptop has 128MB.

 

[[email protected]]

If you object to the coin cell, remove it and wire in a series pair of AA cells
(assuming the coin is 3v, of course). The last time I did this mod was in 1999,
to an IBM PC-AT. BIOS was still fine yesterday when I used that machine to
assemble some MC68705 code.

I might just do something along those lines.

My NEC 486 laptop's lithium battery's shot, and the battery in my
Pentium II-366 MHz laptop is starting to go on the fritz...

On a positive note, though, I finally got my PII laptop to
remote-control my main desktop machine last night (using vnc... that
Microsoft Remote Desktop Connection didn't work for me)

- Another Michael ;-)

 

[Tim Auton]

And you think that all those 64M bytes are being used? Hardware guys put on
enough memory so software guys have plenty to waste.

If you're running Mac OS X or Windows Vista then you probably are
using a good chunk of it.


Tim

 

[[email protected]]

I have not noticed any video cards which use 1G of memory where a mere
64M would do.


Best regards,
Spehro Pefhany

Say it isn't so! When you run Unreal Tournament 2004 or Quake 4, that
GB of video ram can come in handy!