Unidentified CPU Usage At Idle (w/images)

Performance And Reliability Monitor total CPU usage is higher than the
combined processes.
There is something mysteriously using the CPU.

I let the computer idle down and took a snapshot so you can see all
processes running:
http://cid-d82a3813e9bd0e49.skydrive...s/IdleHigh.png
You will see the CPU claims to be using a total of 33%, however you will
notice there are only 2 processes with a combined usage total of 8%.

Next, I reboot my computer, let it idle down and take another snapshot:
http://cid-d82a3813e9bd0e49.skydrive...es/IdleLow.png
This is the result we should expect.

I do not know what conditions must happen for this seemingly random event to
occur.
Is there something else I can do to further this investigation? Perhaps
something in systernals would give more information when this problem happens
again.

Nathan