Here is a recent thread about problems caused by dust build-up inside the machine (also includes a picture): viewtopic.php?f=22&t=16800
. The fan is located under the motherboard, with the exhaust simply blowing into the machine (to the front & left side as I recall).
Well, i have a navibot light for a few months now, and I do see the dust problem coming.
When i do my routine cleaning, i observed that the rubber lips on the body is not mating perfectly to the slot on the dustbin (see the rectangular short wall (or ribs) enclosing the slots, on the blue cover.
There seems to have free ambient dusty air getting into the electric motor directly, without passing through the dustbin and filter.
I pasted a strip of rubber pad, thick enough to go flush with the rib height on the blue cover of dustbin.
And I do not see dust stain around the rubber lips any more.
If this stay true, it is a design failure on Samsung's part.
They design it to fail.
And I read somewhere in this forum that someone from Italy was not given the motherboard warranty, with reason that the motherboard failure was due to dust at customer's fault.