Something is causing it, and often times I find it is things like virus scanners or some program designed to do regular activities. That is where I would start. Any program that you leave running for long periods of time is suspect and should be evaluated thoroughly for this sort of thing.
My Mac Pro running Snow Leopard (10.6.
keeps waking after being put to sleep using key command, roughly every 30m. It is a "full" wake - i.e. monitor on, fans blowing, etc. and will not put itself to sleep again
It's connected to my LAN via a router and to a printer (switched off).
I don't like the idea of the power consumption and HD wear this will be causing. Any ideas?

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