2 out of 3 iMacs died recently. Both were a year old. What is going on?

Question

I purchased 2 new iMacs last year and both have died. One required a new hard drive and a new screen. The other one was dead when I walked into the office today. Is there a problem with others as well? Fortunately they are covered by Apple Care but I'm a little worried they will do the same thing a year from now once the warranty is over. Everything is backed up, I am just concerned about longevity.
-- Linda

Answer 1

Long, highly technical, nuanced article a lot of which is way over my head. But there is this:
protection do you need? A discussion of the power protection requirements of today's computer systems invariably involves references to the CBEMA curve, named for the Computer and Business Manufacturers Association, which was renamed the Information Technology Industry Council in 2000 (Fig. 1 at right). Although this graph illustrates the degree to which electronic systems should tolerate voltage variations, its application has two fundamental shortcomings.
_First, most modern computers use switched mode power supplies (SMPS) capable of tolerating voltage variations much higher than those shown in the curve._
http://ecmweb.com/powerquality/electricavoid_commonmistakes/
Roger: both of our reports are completely anecdotal; certainly, statistically nothing to bet the ranch on, but I have seen what appears to be a disproportionate number of possibly heat related failures of one kind or another for the 24s right here in this forum.
Message was edited by: WZZZ