[c-nsp] Can "power-on" mean anything other than power on?

[Howard Jones]

Hi,

Please could I get the confirmation of  your collective experience?

We have a group of three older Catalysts at a customer site that 
apparently reboot all together (within a second) and for no reason every 
10-15 days or so.

On each switch, for show version it shows:
   System returned to ROM by power-on
   [...]
   Last reset from warm-reset

Can this mean anything *other* than the obvious reason that something 
onsite disconnected the switches from their power supply (bad PDU, 
breaker, cable, office cleaner etc)?

I'm hoping that it can't, because it would be a much simpler explanation 
than anything software-related that affects two different switch product 
ranges and two different IOS versions, but I was curious for a second 
opinion before we get the witchhunt going ;-)

Thanks in advance for any confirmation or extra info,

Howie