[ltp] T20 won't start

[Henrique de Moraes Holschuh]

On Mon, 28 May 2007, Michael Karcher wrote:
> turn it on this morning. Unplugging batteries and AC for some hours
> (CMOS battery stayed in), the machine again works like a charm.
...

> 1. I have ACPI problems since 2.6.21-rcsomething (running git kernels).
> Sometimes after resume, I get no ACPI interrupts any more, also timeout
> error messages concerning EC access, but works mostly. Turn-off on
> resume has been observed sometimes, but an immediate restart using the
> power button was possible. I currently (on AC, batteries charged) can't
> reproduce it just now, but I also had it with the current git kernel
> (2.6.22-rc1 + git patches).

Make really sure you have the latest T20 bios and ec (IBM calls it
differently in the t20, I believe they call it "slave controller" or
somesuch).

Check if using "shutdown" instead of "platform" for the sleep-to-disk method
won't fix the issues.  It might, and many thinkpads seem to react very badly
to "platform" the way 2.6.21 is doing it.

> 2. This machine works on two mainly dead batteries (an original IBM
> ultrabay battery, probably around 5 years old, bought used, ACPI

This will damage your hardware even further, you know.

> 3. I have a defective DIMM installed, but the defective areas (around
> 25M and 108M) are excluded by memmap kernel parameters.

memtest it regularly to make sure the areas have not spread, and that DOES
include the bit decay test, which takes a damn big while.  Also, defective
DIMMS might have cells shorted, which causes a lot of increased current draw
when you hit them (in refresh, etc).  This is guaranteed to cause
suspend-to-ram to go bananas, as the memory modules themselves will refresh
during S3, and hit their bad cells...

>  UseSysfsPowerState mem
>  PowerdownMethod platform

Try "shutdown" (or "poweroff", I always forget).

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh