Good grief . . .
Vacuums create static electricity, that has no place anywhere near integrated circuit boards and sensitive electronics.
The only effective way to clean dust from interior computer space is by opening that space up, preventing fans from spinning, and using an air-stream to blow the dust off of components.
I routinely clean the computers that I service. I use a air compressor. Fans are one of the places that corners are cut to maintain margins. They usually do not have sealed bearings.
When you clean a computer or a Power Supply Unit with compressed air, you must prevent the fan(s) from spinning. You do not want to over-speed the fan and burn the bearings. You also do not want to allow the fan to spin while there is debris in the air-stream passing over the fan, this debris will find its way into the racings. If the fan is spinning, the debris will become part of the bearing/racing assembly and the fan will never be the same.
The only thorough method for cleaning a computer is to open it and have access to the innards. It is not what the OP wants to hear, Hell, it isn't what I want to hear, but that is the truth.
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What type of vacum would be best? I have a mac mini and I wonder if it could get damaged by the strength of the vacum.
When using a vacuum, just remember, the second component to be sucked off of the circuit board voids the warranty.
Just use a Sears 16 Gal shop-vac.

