Air duster/Compressed air, always suitable for PCB's?

[watercooled]

Why not use a CO2 fire extinguisher
Just kidding. I use a vacuum cleaner set as low as it will go and without any tools to keep the suction as low as possible. Avoid touching any PCBs and you should be fine. Take fans off heatsinks and suck the dust out from the fins. Also remember to stop fans from spinning because of the vacuum - it could damage them. Using air dusters just blows dust around the room and makes you cough and gets back into the PC anyway - if you are going to do it do it outside and keep it to short burst of gas - longer bursts could supercool components and damage them (also let your PC cool before using compressed air and keep the can upright). There are risks with both methods.

[AD-15]

To be honest, I'll only really be using the air dusters on my PC very little. The main reason I bought the (cheap) pack is the highly entertaining result when the canister is held upside down.

Nothing is more fun than freezing everything in sight with liquid air (or whatever it is that is used).