acpi won't work on HP 2140 Mini Note

[thyrc]

Description: Ubuntu jaunty (development branch)
Release: 9.04

acpi doesn't work on a HP 2140 Mini Note out-of-the-box. (I had to boot with the acpi=off option in grub, which caused problems when shutting down or hibernate.)

Workaround:
To get acpi working you have to disable "Fan Always on while on AC Power" in the BIOS.

[Jonathan Ernst (jonathan.ernst)]

Does it work if you disable dual-core in the BIOS ?

[thyrc (thyrc)]

Sorry for the late reply..

> Does it work if you disable dual-core in the BIOS ?

Yes, it does!

The same was reported by dixon on the ubuntu forums http://ubuntuforums.org/showthread.php?t=1122347 and http://ubuntuforums.org/showthread.php?t=1115691

[Jeremy Nickurak (nickurak)]

Related to https://bugs.launchpad.net/ubuntu/+source/linux/+bug/376728 ?

If you boot with dual-core ENABLED (which you have to do to get hyper-threading support for full performance), but with the power supply UNPLUGGED from the netbook (not just the wall end), do you get past it?

[dwchapin (daren-chapin)]

@Jeremy: I can confirm this. It boots fine with dual-core enabled and the power supply out. However if AC power is in during the first portion of the boot, you get a stack trace and the boot freezes.

This is on Kubuntu Jaunty. I also have "Fan always on while on AC power" disabled in the BIOS. Interestingly when I boot this way (no AC w/dual core enabled) the fan does seem to stay always on all the time. Though it finally shut off when I slept and subsequently woke up the machine (which worked fine).

[Jeremy Nickurak (nickurak)]

As per the bug that I just marked as a duplicate of this ( http://bugs.launchpad.net/ubuntu/+source/linux/+bug/376728 ), this appears to be fixed in 2.6.29/2.6.30 kernels.

What's required to get this fix backported to 2.6.28 I do not know.

[Jocelyn Habib (jhabib)]

what is the best way to upgrade to 2.6.29 is it stable