[ltp] Re: [T410s] Fan running constantly

[Daniel Näslund]

On Thu, May 19, 2011 at 01:00:15AM +0100, Richard Neill wrote:
> 
> 
> On 18/05/11 20:45, Daniel Näslund wrote:
> >On Wed, May 18, 2011 at 2:37 PM, Stefan Monnier
> ><monnier@iro.umontreal.ca>  wrote:
> >>>When googling, I find several forum posts describing the T410s fan as
> >>>noisy when running Linux but it appears as  a non-issue for Windows
> >>>users.  Has anyone found a workaround? I've found [2] but I'm resistant
> >>
> 
> You can use tpfand / tpfan-admin to control the fan trip points.
> It's certainly safe to run up to 75 degrees (and possibly 95 if you
> feel like risking it) - as long as you run the machine on a table.
> The need to stay below about 45 is to protect your legs (low
> temperature burns), not the CPU. 

As as I said previously, I'm mainly looking for solutions that does not
demand userspace daemons for controlling the fan speed. For the record,
how long have you been using tpfand?

> You might also consider re-doing the heatsink thermal compound, and
> checking the GPU cooling is good. 

Might do that if everything else fails. Just read that the T420s is
supposed to have a redesigned fan [1]. That strenghtens the hypothesis
that the cooling system for the T410s is not optimally designed - if it
were then why would they redesign it for the next release?

[1] http://www.lenovoblogs.com/insidethebox/2011/02/thinkpad-t420s/
> 
> Also, use powertop - it gives helpful advice on what is consuming
> power. It should be possible to get the machine to idle on  < 10 W.

Yes, powertop is a great tool.

Daniel