When you switch to new PC, is it wise to reuse power supply of older PC in new PC? Is it worth using a power supply with years of use on a brand new PC?
Many older components can be used again when you upgrade to new PC. You can use RAM memory sticks, storage drives and SSDs but you cannot use processors and motherboards.
But can you can reuse power supply of older PC in new PC? Answer is yes, but you should pay attention not only to its total power, but also to what current intensity it is capable of generating on the + 12V rail.
It is recommended that you subtract 5% per year of life. So, if you had a 600W source that delivered 48A on the + 12V rail, but is now 5 years old. In that case you should subtract 25% from the values, and we would be left with the equivalent of having a 450W source capable of supplying 36A on the + 12V rail.
Another thing to consider are high temperatures. If power supply is of good quality and is from a manufacturer with a reputation for reliability and you have never forced or maintained it at high temperatures, you should have no problem.