Date: 2016-09-24 09:58 pm (UTC)
From: (Anonymous)
A user on Lenovo's forums is running Linux on a SD card on the ISK2 Yoga 900 and said this about the battery life when I quoted your April article about Haswell and Broadwell power management policies:

Matthew's stuff about the PCH power states is interesting. Taking his numbers (which might not be for Skylake) the change in 'idle time' for a 66Wh battery (like in the Yoga 900) between 5W and 8.5W is 13.2 hours and 7.7 hours. Going to go out on a limb here and say that Skylake is probably more efficient.
Any activity on the machine will of course make it use more power.

I've had mine running all week with Ubuntu and off the charger for several days... so sleep works obviously. I'm not noticing any thermal issues which would worry me more. I'm about to start compiling kernels on it so we'll see how that goes... if anything is going to push the thermal management it's that.

I guess what annoys me about all of this is that Lenovo could have just stated this up front; made the patched BIOS available and with the disclaimer it might negatively affect battery performance and cause more thermal throttling. I would be perfectly happy with that... I don't do many eight hour solid sessions on a laptop away from power. YMMV.

What's more annoying is that if you go and read the Intel forums they say go and talk to the Linux kernel developers... and then the kernel developers say Intel doesn't provide the details. Intel have been doing some great work with Linux lately but obviously this isn't one of those areas...
Identity URL: 
Account name:
If you don't have an account you can create one now.
HTML doesn't work in the subject.


If you are unable to use this captcha for any reason, please contact us by email at

Notice: This account is set to log the IP addresses of everyone who comments.
Links will be displayed as unclickable URLs to help prevent spam.


Matthew Garrett

About Matthew

Power management, mobile and firmware developer on Linux. Security developer at Google. Ex-biologist. @mjg59 on Twitter. Content here should not be interpreted as the opinion of my employer.

Expand Cut Tags

No cut tags