Think GREENER, what is the point in changing a machine which still corresponds to end user needs ?

The problem is that if you don't know when to change your machine, you don't want to go against accounting rules which state that a machine should be changed every three years.

Now you can simply prove the machine health and maintain it allowing to save Millions in your 5-6 years budget. The other benefit is that the planet will save the carbon cost of all the steps from building a PC, up to getting it up and running on  your end user's desk. For doing more or less the same thing than with the former machine.