Short Answer
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The short answer is: yes, if it is not on an enterprise site.

Long Answer
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I have hosted numerous servers on old desktop hardware, there is nothing wrong
with this. Old computers can make excellent file, Minecraft, and web servers.
However, if you are honestly asking the question “should you run a server on
desktop hardware” it implies you are running something important. Don’t get me
wrong, running a Minecraft server is **very** important, however, it is not as
important as a production web server for a larger company. In that case it is
better to have an actual server with redundant power supplies and hot swappable
hard drives.

Another factor to seriously consider is your internet speed. When I was in
seventh grade I ran an apache web server on my old computer. Since I was running
on DSL, the website loaded like it was 1990. If you need high bandwidth, I would
recommend you get a VPS at Digital Ocean.
