Interview question - Power & Area

One day you are strolling the hallways in search of inspiration, when you bump into a person from the marketing department.

The marketing department has been out surfing the web and has noticed that companies are advertising the MIPs/mm2, MIPs/Watt, and Watts/cm3 of their products. This wide variety of different metrics has confused them.

Explain whether each metric is a reasonable metric for customers to use when choosing a system. If the metric is reasonable, say whether "bigger is better" ( e.g. 500 MIPs/mm2 is better than 20 MIPs/mm2) or "smaller is better" (e.g. 20 MIPs/mm2 is better than 500 MIPs/mm2), and which one type of product (cell phone, desktop computer, or compute server) is the metric most relevant to.

Sol:
 MIPs/mm2
Unreasonable: with performance we care about the volume of a system, not its area.
 MIPs/Watt
reasonable: bigger is better; e.g. cell-phone
 Watts/cm3
reasonable: smaller is better; server farm