Originally Posted by
Niku-Sama
Given enough time everything electronic will give up the ghost with out replacing some components. That being said the caps on a nes avoided the capacitor plague (that came after) but they are in their twilight years.
They generally aren't a cause of concern as of yet but will become more of a problem here soon.
That being said there are a few instances of them going bad, from my experience the big one will go bad and cause odd problems.
If you were to take a stab at it it wouldn't hurt to start with that.