You can usually get a few good years out of your IT infrastructure before upgrading. Tech companies have figured out how to create devices that store and process data far more efficiently while using a fraction of the energy that was previously required. You should regularly evaluate your servers to see if one is using more power than it should. If you have a device that seems to be running hot, its time for an upgrade. If it takes up too much space, it’s time to upgrade!”]
Source: http://www.globalhn.com/blog/signs-infrastructure-needs-upgrade/