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[ubuntu] High CPU usage but no processes using it?

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http://ubuntuforums.org – Hi I have recently installed ubuntu on my laptop (Toshiba A300D, Dual AMD Turion, 64bit 9.10 ). All is well but after a seemingly random period of time the CPU usage will shoot up, usually settling between 70 and 100% usage. The weird thing is when I go to any of the process viewers, nothing is using that much CPU! Even in top, the highest any of the processes are using is normally about 5% Memory useage stays low, no swapping and no hard drive activity. It's really annoying as the laptop will start fine then after a while this CPU usage bug kicks in and it slows the laptop down. The only way I can stop it is to reboot. I've looked in the system logs and nothing is being reported there. Does anyone know what is causing the CPU usage to sky rocket and how I can stop it? I'm guessing it might be some sort of stuck IRQs or other hardware calls, as no single process is using this much resource. Any suggestions welcomed! Thanks (Hardware)

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Submitted by colm on 11/06/2009 – Made popular on 11/06/2009

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