On Sun, 24 Sep 2006, Pavel Machek wrote: > I made some quick experiments, and usb still eats 4W of battery > power. (With whole machine eating 9W, that's kind of a big deal)... > > This particular machine has usb bluetooth, but it can be disabled by > firmware, and appears unplugged. (I did that). It also has fingerprint > scanner, that can't be disabled, but that does not have driver (only > driven by useland, and was unused in this experiment). > > Any ideas?
(I have not followed the thread, so bear with me if I say anything irrelavant) I have encountered at least 3 hubs (2 usb2 & 1 usb1) that will consume a lot of power (about 2-2.5W if the laptop power consumption readings are to be trusted) and heat up a lot (to the point of being too hot to touch for more than a few seconds) even when no devices are connected, at least on Linux. I have not tested them on a Windows machine to see if this is the case there. The USB2 ones used Cypress chips. I do not know what your h/w config is, but perhaps this is a similar case ? Regards, Theodoros Kalamatianos PS: Note that the 2-2.5W consumption is the maximum that the laptop USB port can provide, and I have noticed that with the hub's external power supply connected it heats up even more. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
