[ltp] Power drain with ACPI

[Joel Ebel]

I have noticed this on mine as well, though not in Linux.  I still use 
APM in linux, and it doesn't use the battery as quickly, but in Windows, 
if I suspend the laptop, the battery runs down very quickly.  I wasn't 
sure what was causing that, but since it didn't happen in Linux, I 
figured it was just some windows problem.  Now I'm curious though, 
because I hadn't thought about the fact that Windows uses ACPI and Linux 
still uses APM.  Maybe it's an ACPI issue.  This deserves some more 
exploration.  Can you possibly test it with APM to see if it occurs then?

Joel

Yip Wai Peng wrote:
> Hi all,
> 
> I'm currently using a T41 with ibm-acpi and acpi compiled into kernel. 
> Whenever I do a suspend to ram, I've noticed that although it has been 
> suspended, it still drains about 20% power per hour. The laptop is also 
> constantly warm, as if some device is not fully shut-down. (I know ram is 
> still powered but that shouldn't produce that much heat right?
> 
> I am wondering if anybody has the same problem? Also, is the anyway to check 
> whether which device have not been suspended? 
> 
> /etc/acpi/actions/sleep.sh: 
> 
> #!/bin/bash
> 
> /etc/init.d/cpufreqd stop
> modprobe -r uhci_hcd
> modprobe -r ehci_hcd
> 
> echo -n mem > /sys/power/state
> 
> #/etc/acpi/actions/battery.sh
> modprobe uhci_hcd
> modprobe ehci_hcd
> /etc/init.d/cpufreqd start
> 
> Waipeng