HPET problems

I have a Compaq Presario F700 laptop. I love it. The only issue I've run into with it, that's hard ware related, is a weird tendency for the boot process to stutter while under battery power. When not plugged in and booting there are several points where it freezes and I have to press a key to get it to continue booting. This happened both while running Ubuntu 8.10 and 9.04 and Arch, each with the latest kernel at the time. So I'm pretty sure it isn't software related.

I did a lot of searching online and came to the conclusion that it was an issue with how my processor (an AMD Athlon™ 64 X2 Dual-Core TK-57) implements the kernel's High Precision Event Timer (HPET). I've been testing out a fix where I just disable it in the grub kernel options and it reverts to the Programmable Interval Timer(PIT) . Andreas Hermann talks about some pros and cons of doing this in an LKML thread. I haven't noticed any draw backs since I've started testing so I'm pretty confident with this solution. Anyways, try it out if you have a similar issue. Let me know how it goes.

Update Dec 18, 2009: Fixed in Ubuntu 9.10 (Karmic Koala).

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