[ltp] undervolted T43 does not resume from suspend-to-ram when on battery

[Laurent Gilson]

Hello

> two weeks age I undervolted my T43 with the unmodified example kernel
> patch (Alternative 1) provieded by

running that patch for 2 months now (R51).

> Yesterday I tried to wake up my Thinkpad from suspend-to-disk without
> AC connected .
> The system came up but screen remained still blank.  Only the ACPI event
> for the power button was generated, so I could reboot.

Something like that happend to me too. If you undervolt too much the  
system frezes/goes south at start/resume on batt. I assume the power  
consumption and voltage spikes are higher at that time. On my system is  
always happens just after grub.

> After reboot (still running on battery) system came up but showed
> strange error messages about wrong cpu frequency settings.
> I inspected /proc/cpuinfo and found a crooked frequency value.  It was
> about 377MHz (normally it is the default max value of 1862MHz).
> Frequency scaling was not activated at this time.

(If you really want a low-power/high runtime system enable it)

cu