Sure it is, I do it all the time. It's safe to use on you whole computer.
Packers - Penguins - Gators
Like Graph said, they're perfect to clean components with, just some tips:
1. Turn the computer off and unplug it from the wall.
2. Do not tilt the can or turn it upside down, the liquid CO2 will rush to the top and spray all over your components. This isn't necessarily a bad thing, especially if the computer is turned off and unplugged, but it's better to be safe than sorry.
I was an idiot and tilted the can once, luckily the droplets hit my case and nothing else, but they blistered the paintwork (maybe this wouldn't have happened with a less cheap-as-it-gets case).
i7-6700k 4.2GHz | Gigabyte GTX 980 | 16GB Kingston HyperX | Intel 750 Series SSD 400GB | Corsair H100i | Noctua IndustialPPC
ASUS PB298Q 4K | 2x QNIX QH2710 | CM Storm Rapid w/ Reds | Zowie AM | Schiit Stack w/ Sennheiser HD8/Antlion Modmic
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