>> So my next question is... why does a digital device require so many 
>> millions of resisters and capacitors?
> 
> Can't say for all designs, but I know on our LCD electrical designs it 
> is mainly for noise-reduction and filtering.  If we didn't filter the 
> digital signals, especially the ones on long tracks, we would be above 
> the EMC noise limits allowed.  In a car in particular, the FM receiver 
> circuitry is usually right next to the LCD, so the 85-110 MHz band is 
> extra important, I imagine most consumer devices have similar requirements.

Well, I'm looking at a graphics card, so presumably it's to isolate any 
noise from the AGP bus from the (much lower frequency) video signal?

>> I assume the tiny ones *must* be mounted by machine?
> 
> It's done by a "pick&place" machine:
> 
> http://www.youtube.com/watch?v=M7w5OUXwTZs
> http://www.youtube.com/watch?v=6NamGXOgb5s

That's pretty insane...

Presumably the through-the-hole stuff is done by a human operator. 
(Indeed, I worked on a production line doing that once...) The 
surface-mount stuff is machine. Or that would be my guess anyway...

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