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I've got an Ubuntu 11.04 installation on a brand new HP dv6t laptop. When I pull the charger plug, the system knows that it's on battery and seems to apply the power management rules I've got set up. Nevertheless, sitting at idle I can see the battery charge percentage indicator dropping the number by about 1% a minute. I don't expect stellar battery life, but that seems wrong.

I've verified with the "i7z" tool that my CPU is definitely being clocked down when it's idle. I'm not using the ATI graphics adapter in the laptop (because the drivers don't work). I don't see any stray background processes running, just the things I expect, and the load average while I watch the battery drain is always almost zero.

What I'm wondering is whether there are any diagnostic tools or techniques that can narrow down exactly what it is about the electrical situation in the machine that's consuming so much power. I've thought about trying a live CD from some alternate distribution, just to see if it'll behave the same way. Are there any other things to try?

(Yes I realize that it could be a dud battery, but it's really brand new so I'm going to consider that to be unlikely for now.)

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Thanks - no, I'm not aware of that, but I've got a Lenovo laptop (U460) running Natty and it gets about 4 hours of battery life on a full charge. – Pointy Jul 3 '11 at 15:59
afaik it doesn't affect all systems, case in point your Lenovo isn't affected, but the HP is ( I'm assuming that, for the time being). Have a look at the linked post, Phoronix has their test suit which I believe should show the power guzzlers – Sathya Jul 3 '11 at 16:18
Yes cool I've been looking at those articles. I need to RSS that site :-) Thanks very much; I'll try it out. – Pointy Jul 3 '11 at 16:24
up vote 2 down vote accepted

Try powertop. It shows most power consuming processes and gives you hints on how to reduce the power consumption.

share|improve this answer
OK, I will! Thanks. – Pointy Jul 3 '11 at 21:11

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