The oldest computer I have is a 2009 mac mini, which still works, but it gets hot and it's pretty slow. The second oldest is a 2011 fujitsu esprimo e900 which has unreliable capacitors, and has to be plugged in for a while before it can boot up without shutting down randomly. My point is, computers are fragile, even more so the newer one with smaller parts with tighter tolerances. And with the quick advancement of the technology, I think 15 years is already an excessive lifetime.