I love tippig cows!
I've worked on computers darn near everyday for the past two years.
My excitement comes when something just wont work or atleast wont work properly.
So far there hasn't been a problem that I've had that I didn't fix,excluding device cards with beep errors,but replacing them always worked.
Relaying that info may not be as easy,sometimes obvious is overlooked or even sometimes communcation breakdown.
I've also found that if your going to fix something,you should have spare parts to rule out problem devices, hence;someone gets rid of a computer, get it,even if it's just to learn on.