Latitude E6400 + 9-cell battery + 12-cell slice = Runtime?

I am at a point where it's finally time to consider moving up from my trusty faithful D630 that's served me so very well over the years. I'm not interested in the newer Latitudes; the change in form factor is ugh to me, but that's referring to the latest generation.

The E6400 is essentially a work of art as far as I'm concerned, and I owned an E4300 about 2 years ago and I miss it considerably. My biggest question involves actual runtime expectations if I were to get an E6400 with something like the following (this is either a refurb unit or outright used hardware):

- a P-series Core 2 Duo processor for lower power requirements
- an SSD of some kind, probably a regular old 7200 or even 5400 rpm drive to start
- 1440x900 WXGA+ screen and most likely the standard Intel GMA 4500HD graphics since I believe (but I could be wrong) that the E6400 Nvidia models may have suffered that nasty Nvidia solder issue, not sure if that related to the Quadro models, someone clue me in on that if you know more
- 9-cell internal battery
- 12-cell external battery slice

Now, while Dell automagically spits out these huge numbers for battery life like the following (taken directly from the E6400 product spec sheet):

and of course the disclaimer along with that:

tells me that, realistically and based on many years of experience with laptops, I'll never get anything within 8 hours of that in typical use.

So I'm wondering if anyone else out there has an E6400 with Intel graphics, an SSD or even a hard drive, the 9-cell battery along with the 12-cell battery slice and direct firsthand experience with trying to get a really long run on a single full charge of both batteries can offer their advice or opinions.

Honestly, if I could get a solid 12 hours, and I mean solid in the sense that the laptop would remain on the whole time, doing whatever I happen to be doing (even if it was just playing movies back to back), I would find that not only extraordinary but I'd be this guy...



Am I insane to think it's possible? I know with my E4300 and the 6-cell battery and yes using the Dell Control Point battery profile I was able to get 6 usable hours from that tiny little beast machine on many occasions on a single charge, hence me missing it so much. Was planning to get a battery slice for it but never got around to doing so. I really love that 13.3" size but wasn't able to get a 1440x900 display panel for it so, while I can use 1280x800, I find for the 14.1" display size 1440x900 is absolute perfection for me and my aging eyeballs.

Any info is greatly appreciated if anyone can assist, thanks...

 

From my experience:

Approximate idle power with most CPUs, IGP, SSD, LED screen @ minimum brightness, Windows 7: 8W.

9-Cell capacity: 90WHr
Slice capacity: 84WHr(?)

(90 + 84)/8 = 21.75 (that's where Dell gets their number, I presume)

With light browsing (yes, light is a subjective measure), I was typically able to get say 5 hours on a 6-Cell, pegging light browsing power consumption at maybe 11W.

So if you're doing work and trying real hard to save battery life, you can probably get somewhere (90 + 84)/11 = 16Hrs.

 

I agree in that the claims of super battery life are with idle in mind. I have learned this the hard way when trying to achieve maximum battery life on previous laptops.

 

Commander Wolf, I see in your sig you say you've got an SU9300 in your E6400? I did a quick search for the specs of that CPU and I have to ask:

Why?

I know what it is, but even considering the low power nature of the CPU, was the intention to maximize battery life for your particular use ? Honestly curious here as that seems almost like what some folks would call a "Frankenbuild." And fanless too? Damn... gimme more info on that thing, sounds like something I'd create myself.

Did you make any posts or threads about that machine and why you put it together in that fashion?

(and thanks for the info, it helps...)

 

When I was still using an E6400 as my primary machine, I migrated to SSDs and found out how nice it was to have a silent computer - when the fan was off.

There's nothing to "mod" really, I just installed a BGA-modded SU9300 and disconnected the fan. You can do the same thing with a software undervolted/underclocked T or P series CPU (ie via RMClock), but I felt that a hardware cap on TDP was safer at the time.

I would much rather use i8kfangui if it worked... because tpfancontrol does work is primarily why I migrated to ThinkPads.

At least for me, this didn't save battery life either. The SU9300 I have idles at the same power as a conventional T or P series chip. It may or may not be because it's ES.

I could make a formal post or something if you want, but traditionally there hasn't been much interest... and quite franky I'd say that the bottom line is if you want fan control, buy a ThinkPad. If you want longer battery life, get a smaller laptop/bigger battery.

 

Yah, I got it. There are some ThinkPad x61t units on eBay right now for $125 + shipping, with battery but no hard drive, stylus, and AC adapter and I'm considering one for the Wife but, again, it's always about the battery life and how it never seems to live up to what we'd all love.

I'm still hoping someone actually creates a workable machine soon that'll do 24 hours with typical usage ("typical" meaning decent brightness, web surfing, wireless, etc). It'll probably be Apple that gets their first but, as for it being an actually useful piece of hardware, who knows.

If I can get an E6400 as planned and get that solid 12 hours from it, I'm good to go and won't hope for more (but more is always a good thing with respect to battery life, of course).

We'll see what happens, thanks.