Re: [tlug] Favorite Linux laptops these days?

[Kalin KOZHUHAROV <me.kalin@example.com>]

On Sat, Apr 28, 2012 at 18:45, Lyle H Saxon <llletters@example.com> wrote:
> On Thu, Apr 26, 2012 at 12:13 PM, Raymond Wan <rwan.kyoto@example.com> wrote:
>> I think BIOS still requires a separate battery nowadays.  Should be a
>> cylindrical watch battery.  However, without any juice, the system
>> should still start up.  The computer will just beep and say that the
>> BIOS has been reset.  I don't know how long those batteries last.
>
> So there's a base set of settings that live even if the BIOS battery dies then?
>
First it is not called BIOS battery, but CMOS battery. BIOS is in ROM
(flash these days, so you can upgrade it) and will stay there (close
to) indefinitely without any external power. Your settings (boot
priority, RTC date/time, etc.) are stored in the CMOS
(http://en.wikipedia.org/wiki/CMOS) and this is what the battery is
for. The default settings are stored together with the BIOS on the
flash, so when you "reset the CMOS" by shorting the battery, those get
loaded by default. Whether they work (i.e. you can boot) or not is
another story.

>> I heard they are suppose to recharge if the computer is plugged into
>> power.  But I'm not too sure about that.
>
> They went without power for about eight years (and there was no main
> battery installed).
>
Some (recent) motherboards have a supercapacitor instead of a battery,
or in addition to a battery; old machines have normal battery that is
usually replaceable (some were soldered).

> I'd be interested in hearing if it works.  If it's like mine, there
> will nothing at all - not even an indication of the machine getting
> power (I don't think that both power supplies died, but I suppose
> that's another possibility).
>
Bring it next time to TLUG meeting (and say you do so), I can bring
some hand tools we can open it and look inside.

Cheers,
Kalin.