[Tfug] battery life, power management and windows vs linux

[Jeremy D Rogers]

Well, I finally have my shiny new thinkpad t60 and I love it. Fantastic.
<excuses> Unifortunately I will  need to use some windows-only optics
software, so unlike my last laptop, I left windows installed on it and
made it dual boot.</excuses>

Now as I've been tweaking things over the past week, I noticed that
the battery reports around 5 hours under windows and only 3.5 hours
under linux. So begins my quest. I know many things can suck power, so
I think I took care of all the usual culprits. Here is a list of what
I have working in linux:
- cpu freqency is scaling using ondemand governer (down to 1GHz from 2GHz)
- disks are spinning down using laptop-mode
- wireless radio and bluetooth are off (modules unlaoded and kill switch on)

I did some reading up and I found out that the ati cards like my X1300
require the binarry fglrx driver to control the GPU clock scaling.
Pity I have can't use opensource, but it did help me get from 3.5 up
to around 4 hours on battery:
- gpu frequency scaled down and in low voltage mode

Now I'm stuck. Things I've tried that haven't helped much:
- unloaded usb modules
- unloaded pcmcia/cardbus modules (or issued cardctl eject/suspend)
- unloaded modules or tried physically removing unltrabay dvd drive
- unloaded sound modules

The ultrabay actually seemed to help a little, but overall none of the
above gained much over 4 hours.

I welcome any and all suggestions.
JDR