Should I use an antistatic wrist strap when changing the RAM on my laptop?
Yeah, sure.
I am about to upgrade my laptop's RAM and I'm concerned about using an antistatic wrist strap.
Good instincts.
Is it smart to use one or not very necessary?
Yes, it is very smart.
For us, current matters more than voltage; we can take thousands of volts from a taser without dying, but even 75 milli-amps can kill. But for electronics, it’s the other way around; they don’t mind a (reasonably) higher current, but even a few extra volts and they go *poof*.
What are the chances I could damage my laptop?
It depends on you and the environment, but generally, even when low, the chances are still high enough that when compared to the cost of the computer, it makes wearing one a very good idea, especially since computers generally like only about 3.3–12V, but a typical static shock like the kind you get from walking across a carpet or taking off a sweater and then touching a doorknob (or victim) can have thousands and thousands of volts!
Where can I get one, in store, for cheap?
You can get them at electronics stores (that sell computers), though counter-intuitively, you will usually have more luck with a small mom-and-pop computer store than a big-box store that also sells TVs and car stereos.
You can also find them at electronics stores that sell resistors and soldering irons.
Of course eBay is a perfectly good source; they are available for very cheap, often with free shipping, and because an anti-static wrist-strap amounts to little more than just a wire, even the cheap Chinese ones will suffice.
Speaking of wires, if you need to do some work and don’t have time to get a strap, you can use pretty much any wire so long as it conducts and is continuous (no breaks in the middle). Speaker wire is great, though the cord from a pair of dead earphones, A/V cable, etc. will all do if you have access to the metal on both ends, though of course something that can be twisted/tied/wrapped around is best.
Just connect one end to a grounded piece of metal and wrap the other around your pinkie or wrist (you may want to moisten your skin first to increase conductivity).
As a last resort, you can simply discharge yourself by touching a grounded piece of metal (if you can keep touching it with your foot or something throughout the procedure, all the better).
Most people say to use an exposed (i.e., non-painted) piece of metal on the computer case, but that’s not the best choice. It is generally recommended that you completely pull out the power cord when doing internal work, but when you do that, the computer is no longer grounded.
A better choice to ground yourself is to touch something that literally goes to ground, meaning a piece of metal around the room that connects to the actual Earth. Assuming your location was wired by competent electricians, then touching the screw on a light-switch plate (assuming of course that it isn’t covered in paint) is usually the easiest, and most ubiquitous way to discharge.
Whatever you end up using, make sure to prepare the environment to minimize static beforehand. Move to a non-carpeted area, put it on a table that doesn’t make your arm-hairs stand up when you swipe over it, take off any sweaters/jogging pants/etc., and then discharge and connect yourself to ground.