I will follow all the tips I can find
What an interesting process this has been. Thanks to all those who have posted tips in the past.
I now have my T61/FC14 x86_64 system spending 99.9% of its time with the processors (2.4Ghz Dual Core) ticking over at 800Mhz and 99.6% of its time in C3 state, according to powertop. Powertop does not show a division for C4 state, although I have read of it in various threads. Powertop remarks "Wakeups-from-idle per second : 40.6 interval: 15.0s" - is that good? Not knowing any better, I will say I have done as much as I can to save power.
Powertop also comments "no ACPI power usage estimate available", which means nothing to me - should I be concerned? I know the acronym stands for Advanced Configuration and Power Interface, but that is the limit of my knowledge on the subject.
What I have done so far:
- Ensured 'cat /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor' returns 'ondemand'. This is out of the box for my system.
- Ensured my nVidia settings are 'Adaptive' (System/Preferences/NVIDIA X Server Settings/PowerMizer)
- Used the switch on the front of the keyboard bezel to switch off all wireless devices
- Used a script I found elsewhere in this forum to unload my Bluetooth drivers completely
- Disabled unnecessary services like httpd, hsqldb and postgres
- Disabled my sound card (System/Preferences/Sound/Hardware/Profile = Off)
- Closed a slew of applications I normally leave open in case I want to refer to them. This included several instances of Firefox, each with numerous tabs open, which Powertop reported as causing a large number of wakeups on the processor.
- Switched off the Compiz windowing manager (System/Preferences/Desktop Effects = Standard)
- Unplugged my USB webcam.
- Turned my display backlight down as far as I can and still see to work.
- Adjusted my power management (System/Preferences/Power Management) settings for battery operation to:
- - Put computer to sleep when inactive for: 30 minutes
- - When laptop lid is closed: Hibernate
- - When battery power is critically low: Suspend
- - Spin down hard disks when possible: check
- - Put display to sleep when inactive for: 10 minutes
- - Reduce backlight brightness: check
- - Dim display when idle: check
Any suggestions for further pruning will be gratefully received.
I have read several posts from people who are quoting their consumption in watts. Is there any way of obtaining that figure from the system, or is it a matter of putting a meter on the mains plug?
I am going bush over Easter and plan to do some writing, if the lappy will stay awake long enough to make it worthwhile. If everything goes to plan, I will report back as to how I went with battery life.
Edit: It will be interesting to see how accurate the battery monitor prediction is. After 15 minutes on battery, with the above settings, it reported: "Laptop battery 4 hours 20 minutes remaining (96.3%)". If I really get anywhere near 4 hours, I shall be a happy little camper.