BassBeats :
how can a hoover damage the fans anyway?
1. Touching the fan while it is spinning, and break off a blade.
2. Either air or vacuum will cause the fan to spin. This may introduce incorrect voltage back to the motherboard.
(a fan can be basically a generator)
This is you use a toothpick or finger or similar to hold the fan still.
And your vacuum is NOT as good as a can of compressed air in cleaning the dust off. Not as much air velocity.
And you can't get into the same nooks as you can with the little extension tube on a can of compressed air.