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View Full Version : undervolting/downclocking old laptops? + Interesting discovery with NHC



Sash[DSL]
Apr 2nd, 2007, 11:37 AM
Does anyone know how to undervolt mobile pentium III cpus?
We all know new Pentium M laptops can be undervolted and downclocked dynamicly using HNC or RM Clock.

I tried both on my Toshiba portege 3490(700mhz PIII mobile), rm clock does not detect any multiplier-setting abilities; NHC somehow underclocks my cpu to 120-130mhz but somehow acts on its own, ignoring my commands altogher. In other words selecting different states of cpu performance(max battery, max performace) does nothing. Meanwhile none show any volt setting abilities.

The interesting discovery I made is

a) Testing the laptop for battery life using Battery Eater Pro (opengl scene full screen, hdd writing/reading, cpu @ 500mhz, screen brightness way down) shows steady power decrease from 100%-40% and then a sudden drop to 3% in about 1.5hr. In my experience this is common with older batteries, simply means one of the cells is dead. However, testing with the same settings but @ 130mhz shows a steady drop all throughout the battery graph. What gives?

Sash[DSL]
Apr 3rd, 2007, 01:11 AM
?

cloneman
Apr 3rd, 2007, 02:11 AM
does nhc's alleged underclocking affect performance?

use paragraph spacing. I'm lazy and wouldn't normally read that

lincoln
Apr 3rd, 2007, 11:28 AM
Could be because when it's running at 130 it is drawing substantially less power, therefore doesn't draw as much from the battery. Batteries do loose charge, but I'm pretty sure they still keep enough to run your laptop on a lower setting since it may be able to supply that lower amount of energy. When ur processor is cranked, the battery probably doesn't have enough energy to supply the amount needed so it gives you the battery warning.

Sash[DSL]
Apr 3rd, 2007, 01:36 PM
does nhc's alleged underclocking affect performance?

use paragraph spacing. I'm lazy and wouldn't normally read that

done.


Lincoln, what I wonder is whether or not there is a disbalance of power supply involved amongst the 3 cells in the battery. Your theory explains why it doesn't shut the battery down the way high power draw does; my concern is whether or not one of the cells is actually dead or whether the controller deems it dead as its current is insufficient for laptop's power consumption.

lincoln
Apr 3rd, 2007, 11:44 PM
;4899528']done.


Lincoln, what I wonder is whether or not there is a disbalance of power supply involved amongst the 3 cells in the battery. Your theory explains why it doesn't shut the battery down the way high power draw does; my concern is whether or not one of the cells is actually dead or whether the controller deems it dead as its current is insufficient for laptop's power consumption.

I'm assuming the controller deems it dead because of a lack of sufficient current. I don't know for sure though. Either way though, you need a new battery. Try ordering a new battery from ebay or laptopsforless.com