Maximizing battery life with external monitor (Dell laptop)

I have an e1405 with the extended battery, which is sufficient
for 6.5 hours or so (down from 7.5 when new). This unit goes
back and forth from home to work. At home it's powered - at the
office it is connected to a 22" monitor and the laptop screen
itself is dark.

My goal is to get 8 or 9 hours of battery operation with a dark
screen, which seems practical. In fact, it's not happening. Is
the screen backlight ON? Is there something else running that
should be shut down?

Thanks!

Ike wrote:
> I have an e1405 with the extended battery, which is sufficient for 6.5
> hours or so (down from 7.5 when new). This unit goes back and forth from
> home to work. At home it's powered - at the office it is connected to a
> 22" monitor and the laptop screen itself is dark.
>
> My goal is to get 8 or 9 hours of battery operation with a dark screen,
> which seems practical. In fact, it's not happening. Is the screen
> backlight ON? Is there something else running that should be shut down?
>
> Thanks!

Actually, I doubt it is possible. Unfortunately Dell's site measures
its batteries in WHr instead of mAHr so it's a little tougher to
determine what your max capacity is, but here's some food for thought:
My 53WHr battery is really 4700mAHr, and my minimum current draw is
roughly 1000mA, so at best I could get about 4.7 hours. This was when
the battery was brand new, with the laptop's screen off, CPU idle and
undervolted, and HDD spun down in Linux. Assuming the 85WHr extended
battery they make for your laptop has (47/53)*85 ~ 7.5AHr = 7500mAHr,
then the max you'll likely see is 7.5Hr (like when it was new) assuming
your minimum draw was close to my D610. My year old battery now has a
max capacity of 3660mAHr which means that I'd get about 1Hr less than my
original max time, and this is identical with what you're describing.
Even if you could squeeze a little more current down, I doubt you're
going to get anywhere near 9, though 8 may be possible with a new
battery for the first few months.

On Tue, 12 Jun 2007 15:06:11 -0700, Ike <>
wrote:

>I have an e1405 with the extended battery, which is sufficient
>for 6.5 hours or so (down from 7.5 when new). This unit goes
>back and forth from home to work. At home it's powered - at the
>office it is connected to a 22" monitor and the laptop screen
>itself is dark.
>
>My goal is to get 8 or 9 hours of battery operation with a dark
>screen, which seems practical. In fact, it's not happening. Is
>the screen backlight ON? Is there something else running that
>should be shut down?
>
>Thanks!

One thing that I like about Vista is that it seems to have more power
tweaking options than XP. In the Control Panel Power applet, there is
a "Change advanced settings" link that has many more options that I
ever saw (or found) uner XP.