At first I thought it was coincidental that HD activity intensified when I switched to Automatic updates. So I toggled between automatic and not automatic...and it is definite: Install updates automatically results in more intense (and puzzling) HD activity.
Perhaps; But I don't see how you could come to that conclusion from watching the HD activity light. Windows does a lot of disk I/O for things in the background that aren't Windows updates--Even when sitting "idle". Watch the performance screen for disk for a while. It will show disk activity by file name. Depending on what you have installed, there could be other updates coming in too. Flash Player just had a new release come through a few days ago (6/13 for me).
But, setting updates to automatic will get you more "updates" as I mentioned before. The problem is that you may not want them.
W7 updates once a month(2nd Tuesday)...but between second Tuesdays when no updating is going on, there is definite increased HD activity when update setting is on Automatic.
Most activity is by IE.exe(non-administrator user) and svchost.exe(system user).
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