R-51 Will only run on battery in safe mode, OK with AC power.

[one2lose2]

As the title says, my R-51 works fine on AC power. The battery is good. When the charging cord is removed, it will shut down and begin a continious restatt. It will get to the time that preload switches to the hard drive. This is to say just before the welcome screen or the desktop appears. It has Windows XP Pro, fully patched. I have reformatted and reloaded XP with the same results.

If it is in the restart cycle, on battery power, and I hit F8, I can get into "Safe Mode" and it works fine on battery power and stops the endless restarts.

I have changed no hardware or software before this began.

[cche0691]

Hi one2lose2,

Sounds like corrupted ACPI driver or faulty hardware. Please try update power management driver first. If problem persist, please contact local lenovo for hardware test.

Fred

[one2lose2]

Is there a good way for me to do that testing? I have reformatted the hard drive and reloaded all drivers. I reloaded the battery manager before reformat.  I have tried to run an Ubantu disk under battery power and it will stop and restart. If I plug the power supply back into the laptop when it is in it's restart cycle, it will than work fine untill the cord is removed. I would like to know what hardware to look at.

Thanks for helping,

Jim

[cche0691]

Hi one2lose2,

I think it's better to keep the test in Windows environment, as lenovo(IBM) only put Windows driver online for R51. For hardware, you can try to test DC-in subcard, chipset and even CPU for the cause.

Fred

[Mornsgrans]

You can boot your R51 with a Linux-Live-CD.

If there the same happens, it might be a hardware problem.

Please also note:

The power manager does not recognize all damages in batteries and shows a good state even cells in the battery are dead.

So it might be a good thing to replace the battery ba a known good one for testing (borrowed from other user)

[one2lose2]

Thanks for the answers. More and more I am thinking it is a hardware problem. But, what hardware, and how to be sure of that as the problem. The battery is less than 6 months old. The Linux Live I tried to run from would not load. I am guessing it was because of the power off while it was loading.

What gets me pulling my hair out is that it will run almost 4 hours in safe mode on battery power.

There is some key in that action. But I don't know what.

Jim