It's not all that silly in many cases, but certainly is so when the software is hardware-independent. There are a not-insignificant number of sites running software that's written in C++. In such cases, the program can be OS and even CPU dependent.
For instance, at the company I work for, we have this one server application that has an AMD-specific dll compiled into it.
But I agree that in most cases, the hardware is irrelevant.
OTOH, are they just talking about the class of server you're running on so they can get an idea of how much horsepower they need?
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