[ltp] Re: wireless switch: is off really off?

Shannon McMackin linux-thinkpad@linux-thinkpad.org
Tue, 10 Jun 2008 23:04:36 -0400

Arno Trautmann wrote:
> Hi,
> until a few days ago, I didn’t manage to get my W-LAN running, so I 
> always disabled it by turning the swith to ”off“. But the machine was 
> very warm underneath the fingerprint-reader. (a X61s)
> Then I finally managed to get W-LAN, and found this on thinkwiki:
> -- 
> If you need Wi-Fi, you can also reduce power consumption (at the price 
> of performances) by activating the power saving modes:
> iwpriv eth1 set_power 5
> For drivers using the new Wi-Fi kernel framework (mac80211/cfg80211), 
> the canonical way to do this is now:
> for i in /sys/bus/pci/devices/*/power_level ; do echo 5 > $i ; done
> -- 
> Using this, the machine is much cooler, /with/ W-LAN enabled and active. 
> So what caused the heating? Was it the w-lan card anyhow /not/ disabled 
> by the switch? Or does the last code line change anything else than w-lan?
> I’m very happy now, having temperatures of about 40°C instead of nearly 
> 50°C—but I would like to understand, why…
> Thanks,
> Arno
I've found that the switch only turns off the radio...