>I added noatime to both and yes, it helped a bit - but still the disk
>starts up again every now and then, even though the machine is disconnected
>from Ethernet and doing nothing.  (I killed cron already so it's not cron
>that's writing to disk now..)

Well, add that debugging code I mentioned before and track it down.
It doesn't do it for me, so I'm guessing it's something you run on
your machine.

--Ken