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T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 12:21 pm
by meng747
My T400s consumes about 50% battery during a 12 hours sleep. My battery is old, but even converted into a new battery capacity, it losses 25%.

Is that normal? Does anyone else have the same problem?

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 12:52 pm
by dr_st
I assume you mean sleep, as in, standby, with the moon LED on?

If so, it's a still somewhat excessive, though often explainable within reasonable parameters.

Any "wake up" settings enabled on the Ethernet or the Wifi? You can check in the Device Manager.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 3:23 pm
by meng747
dr_st wrote:I assume you mean sleep, as in, standby, with the moon LED on?

If so, it's a still somewhat excessive, though often explainable within reasonable parameters.

Any "wake up" settings enabled on the Ethernet or the Wifi? You can check in the Device Manager.
By "sleep", I mean Fn + F4 or closing the lid. It might be have something to do with the chip set.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 3:27 pm
by rkawakami
Well, Fn+F4 will put the system into sleep/standby mode but closing the lid may or may not. That depends upon how you have Windows and/or Power Manager configured.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 4:22 pm
by meng747
rkawakami wrote:Well, Fn+F4 will put the system into sleep/standby mode but closing the lid may or may not. That depends upon how you have Windows and/or Power Manager configured.
I did configured my laptop to enter sleep/standby mode when the lid is shut. By the way, I got SSD hard drive. And I added a mobile broadband card by myself. Is that the cause?

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 4:32 pm
by rkawakami
I guess that could be possible. Try putting the laptop into sleep mode with the WWAN card first powered down and see if it makes a difference. You should be able to use Fn+F5 to turn the radio off, or use whatever driver/utility program controls the card.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 4:39 pm
by pianowizard
Are there several sleep modes that you can choose from? For example, the BIOS may let you choose S1 versus S3. S3 conserves more power.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 4:44 pm
by dr_st
I don't think S1 has been an option in the past decade or so.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 4:47 pm
by meng747
pianowizard wrote:Are there several sleep modes that you can choose from? For example, the BIOS may let you choose S1 versus S3. S3 conserves more power.
I didn't see the S1 or S3 option in BIOS, so that might be unavailable for my T400s.

Re: T400s Excessive Power Consumption During Sleep

Posted: Thu Dec 11, 2014 5:46 pm
by pianowizard
meng747 wrote:I didn't see the S1 or S3 option in BIOS, so that might be unavailable for my T400s.
I mentioned S1 and S3 only as examples. There might be sleep states with other names. Look around in the BIOS.

Re: T400s Excessive Power Consumption During Sleep

Posted: Fri Dec 12, 2014 3:41 am
by dr_st
There are not other sleep states and there never have been as far as I know, on any Thinkpad.

Poking around the BIOS doesn't hurt, but I doubt one would find anything there. I've seen plenty of Thinkpad BIOSes.

IMO, wakeup states of the various network controllers are the more likely culprits. They are often on by default, and you can save some power if you don't use these features.