I THINK I have found the culprit!
The laptop is an HP G62 and a built-in program is is the HP Wirelesss Assistant HPWA_service.exe
This seems to be the program that spikes the CPU use every few seconds. Whatever, if I disable the program via Task Manager the CPU use no longer spikes but dribbles along at a few % usage. The laptop seems to run with no problems, indeed maybe slightly better.
A web check indicates that the HPWA files simply tell you when your wireless system is/is not in operation, and MAY be needed for the physical wireless on/off switch to work. In practice the switch button on my machine still works with the program disabled.
Question now - how do I stop HPWA_service.exe from loading every time the laptop is switched on ????
I guess I COULD find the file and rename it - but I seem to remember there is a much more elegant way of deciding allow/ disallow for programs at start up
5 Precepts of Buddhism seem appropriate. Refrain from taking life. Refrain from taking that which is not given. Refrain from misconduct. Refrain from lying. Refrain from intoxicants which lead to loss of mindfulness