I have never cleaned a PC with compressed air before, but I did take my lungs to it and even used a domestic vacuum cleaner, with no issues.
I am concerned about water or fluid from the aerosol hitting the components, and have been told I should only use the can upright. That won’t be so bad, but can I at least bend the straw to get to items 90 degrees above or below?
I know about holding the fan still when blowing into it, btw.
Lastly, should I place the opened PC outside, or nearly outside? I’ve seen the dust that bursts forth from various YouTube videos when the PC is outdoors.
Make sure the computer is disconnected from the AC mains. Sometimes you can get small amounts / drips of fluid from the air can if button is held down to long. Bursts are better. However I have never know this to be a problem and it evaporates fairly quickly in the warm. Yes do not turn the can upside down and spray this will cause the liquid to come out which you don’t really want.
Well its best if you take outside otherwise you are only spraying the dust out of the PC and in to the rest of your house. Depending on the amount of dust you could have a hoover on hand at the same time to suck up the dust as you spray it free.
Another thing to point out is that these air cans, the liquid turns to a gas at room temperature, if you hold down the button for an extended period of time the can will start to get cold and this reduces the rate at which the liquid changes to a gas meaning in short the pressure of the air blast decreases. You will need to let can warm back up to room temperature for it to start working again properly. Hence why blast are better rather than continual spray.