Upon repeated re-reading of my post [both original and update] neither was particularly well done - no, I don't think you're stupid enough to dowse a computer in water [I should have made it clear that I was referring to a fire
near the computer for that sort of thing] but I still think that using a CO2 fire extinguisher to blast a PC is probably going to be only slightly better than pointless at best, and potentially damaging - although CO2 fire extinguishers are designed not to cause static etc, I'd still be concerned about solid lumps of CO2 flying around the inside of my PC.
Incidentally, are you realy going to spend £30+ on a Co2 extinguisher to try this out, or do you have one lying around? I mean, the benefits compared to a can of compressed air seem minimal at best, for example checking fo rstatic air could be done just as easily with a ciggy or a small oil based smoke machine, surely?
PhillyDee is correct also - holding onto the nozzle, or anything in direct contact with the solid CO2 will cause frostbite in seconds, sounds like you aren't stupid enough to not know that though
For all my negativity about it though....I'd like to see a video too

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