Hi
I just fixed a similar problem.
1 - Immediately after rebooting, my Processor useage was 50% (I have dual processors)
This was fixed by going to the service management and disabling HPSLPSVC32.DLL (HP network device support) I have a HP printer.
2 -Then, after a while and no recall of what I had been doing, the processor would act up again, but this time in quick burst mode for about 45% (both processors).
This was fixed by doing Regedit.
I have a Canon Scanner 9950F. Recently, I moved the USB connection and was left with Scanner #1 (inactive) and Scanner #2. Scanner #1 (inactive) was the culprit. It was being polled after using the Scanner.
See Microsoft about a Visioneer USB Scanner:
http://support.microsoft.com/kb/303777
When you have located the device key for your scanner, open the following DeviceData subkey:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Contro l\Class\{6BDD1FC6-810F-11D0-BEC7-08002BE2092F}\0000\DeviceData
NOTE: There can be multiple values in this key, such as, Server and TwainDS.
To change the polling time interval, create a new DWORD value under DeviceDate called PollTimeout, and then set its value to have a polling interval in milliseconds. A value of 1000 can poll every second. The default value is set at 700.
To disable the button functionality and the polling capability, create a new DWORD value called DisableNotifications, and then set the value to 1...................................
I applied the last solution "DisableNotifications" to my Scanner #1....Et Voilà
Hope this helps.
Regards