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After turning on my desktop one day, I found that my CPU usage was maxed out at 100%, with most of that going to hardware "Interrupts":

I tried to enable/disable all my devices one by one through the device manager, and found that I could get the CPU usage used by the Interrupts down to 50% by disabling all devices labelled "USB Host Controller" (except the ones for the mouse/keyboard). I found that I also got 10-20% more from disabling "High Definition Audio Controller".

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Following the tutorial at:

Led me to similar conclusions (that is, that the culprit is mostly "USB Host Controller"):

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I've tried updating my asus motherboard driver and my video card driver. This is on Windows 7 64 bit.

I've spent hours trying to figure this out and I'm running out of ideas short of formatting (which might still not fix it!).

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Can you post screen scap of your Task manager ,showing process running tab ? – Desingh Apr 8 '12 at 5:41
Ok, I've added screen shot of task manager – eventualEntropy Apr 8 '12 at 13:22
I had this exact issue (usbport.sys HDAudBus.sys interupts) on a PC, never did figure it out. Assumed it was a driver conflict that could not be sorted out, tried everything, XP had no issues on my hardware, only… – Moab Apr 8 '12 at 15:09
up vote 3 down vote accepted


All I had to do was update BIOS. I was previously still using the initial version that came with my motherboard. In my case I just had to go to the Asus support site, download the latest BIOS, and then follow instructions that I found here to update it from a USB stick.

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