Hi Marten - sorry it's taken a while to get back with you. As "Nehalem" and Intel AMT are concerned we don't have a bunch of publicy available information yet. I did find a link, however (not on an intel site!) it has this picture of the architecture. This may be the closest we can get to finding you an answer. Check out the links and let us know if it helps.
Hi Gael,
thank you. I think this picture answers my question in the first place.
It seems reasonable to put the Management Engine into the IO-Hub. But I'm curios how the ME can access the system memory when the system is in powered-off or S3 state. Maybe I did not quite understand if the ME does access the systems RAM in powered-off state at all (I'm pretty sure it does to provide the "powered-off services"). The Architecture Guide mentions S3 only.
I can think of two possible solutions (both seem somewhat unlikely to me)
1) the ME can enable the cpu's memory controller for short time periods in S3 and even powered-off state
2) the ME features it's own RAM
Marten