HPET clock is broken on Dell 760 Hardware

[wdc]

When you boot from older Intrepid media, you see an spew of kernel oops messages. The apparent work-around for this is to power cycle the machine.

A one-line change to print the error message only once is incorporated into the Intrepid update kernel, so this symptom only affects systems lacking the update kernel.

The warning is reporting a fault in the HPET clock which *IS* real.
It takes forever for the system to boot up, and logging in takes rather long. The work around is to boot with the option acpi=off.

When you boot Jaunty, even from media as recent as 3/24, you get a blank screen unless you use the boot option acpi=off.

We need to find out where the fault lies and get it fixed.

[wdc]

This turns out to be more than a one-line kernel change.
The kernel change makes the endless spew stop, but does not fix HPET.

The manifestation of the problem is more serious under Jaunty.
If you choose, "Try ubuntu..." from the live CD, you get a blank screen.

Under both Intrepid and Jaunty, you get much better operation if you set "ACPI=off"

I have opened LP 348694
 https://bugs.launchpad.net/bugs/348694

on this issue.

[wdc]

Revised description to reflect current understanding of the problem.

[wdc]

dmesg output from debathena-cluster system with normal code path. acpi enabled, slow response. Notice the oops.

[wdc]

Same system booted with "acpi=off"