Thanks to all who responded to the "best distro for old laptop"
thread . Useful info for me.
I decided to investigate power savings on my main box
(probably got a bit carried away) and the saga is on my website at
http://www.houseman.demon.co.uk/acpipage2
the box had a athlon 1.8 XP cpu and a7v333 mobo + radeon 9600 pro,
2 x ide drive and is on for ~15 hrs a day mainly at idle.
The things I investigated were acpi (no use) , a mobile cpu ,
cpufreq(powernow-k7) , reduced Vcore , and a low power graphics
card (ati 7500) . Also investigated different hard disk options .
from the note , the power used was :
original configuration (in X)
idle 126w
100% cpu 150w
config : mobile athlon 2000XP , powernow-k7 (ondemand) ,
radeon 9600 , Vcore = 1.5
idle 86w (f=534)
100% cpu 113w (f=1668)
new config : mobile athlon 2000XP , powernow-k7 (ondemand),
ati 7500 radeon mobility, Vcore=1.5
idle 72w (f=534)
100% cpu 99w (f=1668)
so savings of ~50w with mobile CPU, cpufreq , low power graphics,
and reduced Vcore (for mobile cpu).
and a summary :
- acpi per se did not do anything for me .
- the mobile processor uses much less power than the original athlon.
- the amd powernow (cpufreq) has made a significant saving of power .
- could not get the voltage part of the cpufreq to work, but the
mobile athlon had a base Vcore = 1.45 vs original 1.65 ,
and so set to 1.50 by mobo jumpers.
- dont know if the original athlon would have used powernow ie is it
possible that powernow works on standard (old) athlons ?
If I were starting again on this process, then I would check
that out.
- needed the create_fake_pst change for the powernow-k7.c code,
and to modify the table to match the processor I had.
- newer athlons use coolnquiet which presumably is at least as good as
powernow .
- ondemand governor had a small bug , but now runs fine.
- the load/unload ide drives could save power as could an
external hard drive (if turned off whne not in use).
- radeon 9600 used ~19w power, old 7500 has mobility gpu and uses ~5w
- a tft monitor could offer similar savings (~50w) over my
glass one, but cant really justify the cost for a similar
sized one (1600x1200) and the saving would be too long term.
On a totally different topic : have upgraded my strace annotator (stan),
to use STL containers instead of my own classes , and fixed some bugs .
As there was zero interest the last time, I aint expecting much
this time either , but I find it helps when reading strace output.
My main use of strace seems to be for debugging config problems , which
occur mainly on (re) install of linux or other major components ,
so use happens in occasional spurts. The last time, stan fell over
and I was motivated enough to try to fix it .
The main things it (stan) does are :
- track open/close/dup/fork etc and annotate what the fd used for
a read/write represents eg the filename for a file.
- tries to check process pipeline for execve cmd and display that
- attempts to detect failed searches for files , and flags that .
it makes checking an strace output file a bit easier, but need a wide
terminal to see it clearly.
The .bz2 file is on my website.
Hope the above is of interest to some one ... I had problems finding the
power saving info that I wanted when I started , so maybe it will help
some one else ... then again maybe not
Cheers,
Steve
--
currently steve at houseman demon co uk
http://www.houseman.demon.co.uk/
(nfs checklist, strace annotator, mobile a7v333,Eastleigh garage recommendation)
Linux