Obvious over-rating is obvious

I was looking at 12V "industrial"-type power supplies, may be useful for mITX builds.

There was one being sold rather cheaply for its output power.

12V, 10A.

However,

Input current: 1.1A @ 115V

Hey... that's only 126.5VA.

I can let it have 99% power factor, possible in this day and age of active PFC, but over 90% efficiency for an AC to DC power supply so cheap? Not likely.

So this thing is obviously incapable of sustaining 120W continuous.

If you observe, a good power supply's (input voltage x current) in VA (volt-amps) is much bigger than its rated maximum output power in watts, in some cases more than twice as much. So this can be a good way to see if the company is padding their ratings.