Slow boot with Clocksource unstable in Hardy Heron

I encountered this problem long time ago, about September 2008. When I chose to boot into Ubuntu, it stuck at splash screen about 2 minutes. In order to view the elaborate boot information, you must remove splash and quiet from the grub menu which come by default.

sudo gedit /boot/grub/menu.lst

find a line that look like this

kernel        /boot/vmlinuz-2.6.24-23-generic root=UUID=84884ca6-fbea-41dc-962d-98577270be8b ro quiet splash

then remove quiet and splash. This will make Ubuntu spit a detail on boot time.

On my Asus M9V (Pentium M), Ubuntu 8.04 freeze at this line.

ACPI: Processor [CPU1] (supports 8 throttling states)
clocksourse tsc unstable (delta=183220173ns)

I found that this was a known bug on Ubuntu Hardy Heron^[1]. Workaround from the launchpad is adding clocksource boot option to grub menu either hpet or acpi_pm (I use hpet). So, your grub menu will look like this.

title        Ubuntu 8.04.2, kernel 2.6.24-23-generic
root        (hd0,2)
kernel        /boot/vmlinuz-2.6.24-23-generic root=UUID=84884ca6-fbea-41dc-962d-98577270be8b ro clocksource=hpet quiet splash
initrd        /boot/initrd.img-2.6.24-23-generic
quiet

Resources:
^[1] - https://bugs.launchpad.net/ubuntu/+source/linux/+bug/190414