pat
Expert
how can u be so dumb? its compressed air, its not acid or anything spray it anywhere inside ur computer and only worry if somthing blows off. in my experience everything that gets a lot of dust on it is very solid and has fans on it, so at most ull spin the fans with the air... so u may wanna buy new fans because itd be unsafe to run them afterwords...
Fans that have ran with lot of dust will likely be worn by the fact they ran out of balance for a while. The dust might prevent to run fast enough to fail, but once cleaned, they'll likely start to make noise and fail