Date: 06/07/07 (IT Professionals)    Keywords: software, web

I have a Toshiba Satellite P35 laptop in my possession. I just blew the hard drive and threw XP SP2 on it. Everything works fine except for one critical detail - when Windows loads, it does not recognize that the laptop is charging. The P35 has three LED's on the front - a green AC LED that indicates the laptop is plugged in and running off the wall, a green power LED indicating the computer is on, and an amber charging light that indicates the battery is charging (not discharging). When Windows loads, the Charging LED flickers once, and about five seconds later shuts off completely, never to return. The AC light is still on, meaning the motherboard recognizes it's running on AC power, but the charging light is no longer on, and Windows thinks its running on batteries.

I reinstalled Windows, thinking that maybe I jarred the power cord loose during installation, and the same thing occurs. I went to Toshiba's website and downloaded the latest software and drivers. I loaded all of that onto a thumb drive, and booted into Safe Mode thinking I could conserve power - well, not only did it conserve power, the laptop charged quite happily, enabling me to install (mostly) everything.

The only way to charge it again is to shut down, pull out the cord, and plug it back in - it will not charge via normal operation through Windows XP. What could cause XP to go stupid with regards to power consumption like that? Is there a hotfix I should know about? Thank you.

~Elliot

Edit: The plot thickens: In order to install Windows updates, my 1AM crafty thinking reminded me that most modern laptops don't wire the battery into the power circuit, meaning you can run the computer solely on AC power without the battery installed. So, I yanked the battery out, booted it up, and low and behold I'm on essentially unlimited power from the wall. After my updates installed, I dropped the battery back in to see if that fixed the problem... and it didn't. Turning it on without the battery, then plugging it in after it boots to XP appears to work briefly, but Windows forgets it's plugged into the wall and switches to battery power again. If you pull the battery out, the system dies; it's like a kiss of death.

It's almost certainly an ACPI issue, which I've not had much experience with. Any ideas?

Source: http://community.livejournal.com/itprofessionals/59246.html