Are that type of static wrist straps good?

If it doesn't connect to ground it won't be very useful. A lot of people just touch the computer case first before working on the internals so they are at the same voltage as the system. That is exactly what I do, I don't bother with a wrist strap, I just touch the case before I stick my hands inside.
 

ricas123

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Dec 5, 2013
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But if all the parts are painted? And where it is the best to place PC when putting it together ? Is it better be placed on wooden ground or wooden desk?
 


It doesn't matter where you set it as long as you touch the metal on the case to keep the voltage that is in you the same that is on the case. If you have the power supply plugged in then it has a ground wire that should discharge the static in you when you touch the case. Now I wouldn't keep the power turned on the whole time when you are working on the internals, this can create other issues.