i once connected by accident a 50watt wire to my MOBO, all electricity in the house went down, so i thought my mobo was fried, but when i tried to boot it again afterwards, it just booted again.... im still using this PC, and it has been 2 years since, so i'm a bit sceptic against this static electricity thing....
here is a pretty good analogy for watts vs. volts: HowStuffWorks "What are amps, watts, volts and ohms?"
This is a better page i think for more detail (and also a stunning picture (pun intended): Watts, Amps and Volts and How To Understand Electricity
I would not work on carpet,or even walk on it without touching case metal.
I don't use a strap but agree with Mitchell it is the Best Practice so we should probably always mention it first.
Once upon a time I was so "illiterate" (lol!), I had a small musical keyboard, I just popped it open (I just love to play with electronics :) ) just to play with the chips in there. It was meant to work at just 6V but I took a 9V power source and started playing around, connecting the 9V source from one point to another on the chip thinking that 9V can't do any harm (I felt so coz 9V never give humans a feel-able "shock", lol). What next? It never worked again. I have no idea of how many micro circuits did I fry.
Oh boy, now I gotta show AGAIN just how illiterate I am. Just finally bought a can of air to de-dust my PC but after reading this am wondering if I need to wait 'til Mon. when the store re-opens & go buy a wrist strap 1st. I just spent a few minutes shuffling around the room(carpeted) & touching several different metal objects but never got any shocks but sure don't want to take any chances with this machine.
Just hold one hand on the metal part of the case while "spraying" the "air" from the can with the other hand. As long a you don't touch anything inside, you won't hurt anything. Just don't let the air blast spin the fans. If you need to dust through a fan, use something non-conductive, such as a dowel or a soda straw to keep the fan from spinning while letting part of your body maintain contact with the case. I've been cleaning my computers for years and have yet to have a problem, even when I only touched the case from time to time instead of maintaining contact. Frequent cleaning will reduce the amount of forcible cleaning needed. This coming from a paranoid, old bi...broad who won't even handle a HHD without anti-static gloves on.
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