I'm of the opinion that solid state technology should really last indefinitely. Anything else should last at least 5 years. Anything else, really, I mean think about it. Stuff should last awhile. The floppy drive in my PC, for example - that, and my keyboard, are old for PC stuff. 1996-old. And they still work. Cheap fans, maybe those will wear out. I only use fans with ball bearings or Panaflo's Hydrowave bearings. They can last for years with constant use.
I guess this is my mini-tirade on how we seem to think of it as "normal" when computers die after only a year or two, just because of their impending obselecence.