T400 terrible battery life (9 cell)

Here's what happened. T400's are supposed to get 5hrs+ battery life on a 9 cell, and that is about what I was getting. Then I undervolted to see if I could get it closer to 7hrs.

Here's the problem. My battery life is getting worse and worse. Not because of the battery itself, but because the cpu never idles. There's always random crap thats using the cpu and hdd so on battery it stays using usually 14+ watts. It used to reach 7 or 8 watts at the lowest with wireless off brightness down etc... At that time, I could still get 9 or 10 watts using it with reasonable brightness and wireless on. Unfortunately this only lasted a couple days. Vista did have slightly better battery life, but it was slow. Currently using w7 64bit. *edit* forgot to say the estimated battery life is now always less than 5hrs, more like 3 or 4. It used to be at least 6, 7 or 8 with lots of power saving stuff.

Any ideas? Could it be mcafee? Even when I stop doing anything the cpu hovers around 10% usage (this is underclocked though).

I don't really want to reinstall the os since I have everything I want on here, but I guess I could if I need to.

Another random problem is when I installed access connections my wireless started taking like 15 seconds to connect after coming on from standby. I uninstalled access connections and I still have the same problem. It's irritating to have to wait that long when I have a computer that's capable of connecting right away (it used to connect right away).

 

Have you tried removing the undervolting software to see if your battery life returns?

 

Do you happen to have switchable graphics in your T400? In a known bug that Lenovo (or ATI in their drivers, for that matter) still hasn't chosen to fix, resuming from Standby/Hibernate will enable both integrated and dedicated graphics modes, consuming extra power. You will need to switch to dedicated, and then back to integrated graphics to switch off the power-hungry dedicated graphics.

 

so what sort of background processes are running?

 

I don't think it was the undervolting software that did it. I think it helped slightly. I have gone back and same thing.

Nope, just integrated.

That's probably the problem. I'll admit, I'm guilty of having a million tabs open in firefox, but even without it the battery life is too short.

Here's what it looks like at minimum power usage. I'm doing literally nothing, just left it to sit for several minutes to let it calm down . Brightness all the way down, wireless card off, all programs closed, optical drive off, maximum power saving settings. At this level I'd expect more like 8 or 9hrs estimated.


Only difference in the next pic is with firefox open, and wireless card on. Even this was near the lowest it got. I minimized firefox and stopped doing anything for several minutes.


Last, this is doing nothing with brightness at 7 (15 being brightest). Wireless is on I think. Once again this is the low, I let it sit there for several minutes.



Right now I'm typing this at comfortable brightness (a little over half). Firefox is the only thing open, again with a million tabs open, and the battery life says 4:22 (89% remaining). It got down to 3:20 or so just doing stuff with the internet.

It might not sound THAT terrible, but on it's best day I'd be getting 5+ hrs estimated with brightness halfway up browsing firefox, 7+ using a word processor with decent brightness, and over 8 with wireless off and brightness down. It seems like if I do anything the battery life jumps down to 2-4hrs which is terrible for my battery. Just in the time I've taken to read through this thread, take screenshots and type and edit this post I've burned through 15% of the battery (yes, it's at 85% now). It says in the low 4hr range unless I do something like change tabs and it jumps down to 3 something hrs.

 

Any ideas?

 

What's your battery condition like, and how long have you used it? Look especially at the cycle count and the reported charge capacity versus the design capacity.

If you've got plenty of cycles you might want to consider doing a battery gauge reset, as the numbers get thrown off a considerable amount over use. At least that's from what I've read, but that is kind of a last-ditch effort sort of thing and something you don't want to do very often at all.

 

What exactly does a battery reset (specifically in the ThinkPad context with the Power Manager) do and why is it unadvisable to do it often or at regular intervals? Thanks.

 

The Task Manager screenshots you posted, while helpful, are only displaying the processes for your account—you might have processes started by SYSTEM and related that are using CPU time. In addition, browsers eat CPU time too—using often-useless marketing-oriented Flash and JavaScript animations.

 

it basically fully discharges then recharges the battery, it allows the battery's controller chipset to know what the actual minimum and maximum charge level is, and calibrate the value accordingly.

 

undervolting it might cause the clock speed to fall too much and thus cause higher processor activity. The fact is that if you have any Flash websites open or even just regular Firefox cruising you're going to be chewing through CPU cycles, and if you downclock it too much, you're going to have higher processor activity for longer periods of time. Also your Firefox is chewing through your RAM and eating up lots of clock cycles, so i'd suggest Flashblock, Adblock Plus, or Noscript to prevent your browser from eating through your processor.