That depends on things like usage period, warranty, overclocked or not, physical state, person who used it and the usage(heavy or light or carefully) & etc. You need consider those if you gonna buy a used one. And You need to be more careful about some specific parts like HDD,SSD,PSU,GPU and MB (specially moving parts).
Like others said new is better, but if you can find barely used parts for reasonable prices then go for it, and keep in mind about above facts.
As said above new is always better. But most the time refurb is just fine (depending from where you get it) and always cheaper. Bought a refurb GPU a while back, thing runs just as good as new today.
That depends on things like usage period, warranty, overclocked or not, physical state, person who used it and the usage(heavy or light or carefully) & etc. You need consider those if you gonna buy a used one. And You need to be more careful about some specific parts like HDD,SSD,PSU,GPU and MB (specially moving parts).
Like others said new is better, but if you can find barely used parts for reasonable prices then go for it, and keep in mind about above facts.