I was just wondering , for those that have flickering issues. Does the flickering occur during the running of certain programs or does it flicker while just showing the desktop ? The reason is , I have not seen any flickering on my 27" i7, and I would like to test it running a program that causes flickering, if there is a certain one. I only use Aperture, CS4, Mail and Safari. The only screen blackout I have had is when using a certain filter in CS4. That filter caused my previous iMac to hang when I used it, so I blame the software on that one.
I think your query illustrates an interesting point. It seems like this flicker issue may be the perfect
nightmare scenario for engineers. Consider:
In many cases, the flaw manifests itself only after extensive use (days, weeks, months?), often occurring, then spontaneously resolving, only to reoccur later. It doesn't seem to be associated with any particular software, CPU type, CPU activity level, temperature, or GPU (i.e., the flaw's not replicable. In software-land, these kinds of problems can be a real bugger bear.) It even persists in some cases after replacement of various hardware components. I have yet to read an explanation for this problem that sounds satisfyingly plausible--despite the obviously large number of Mac experts who cruise this forum.
It's hard to judge by forum post counts and self-selected surveys, but for the sake of argument let's assume that the defect is affecting perhaps 5 units per hundred. That's large enough to cause an outcry from thousands of angry users, but it's also small enough to slip through standard pre-production testing as well as assembly line quality screening.
In my opinion, Apple engineers have now identified the problem and are retooling production to incorporate the fix. I suspect the problem has nothing to do with Apple engineers being stupid, lazy, or greedy, although I could be wrong. I also suspect Apple will have to extend the standard warranty to cover this defect (if it manifests after 12 months), although I could be wrong about that too.
Anyway, I'm postponing purchase of our two new iMacs, waiting for the online Apple store's estimated shipping times to start dropping and for a wave of 27" refurbs to show up. My strategy seems like a reasonable precaution, unless you just gotta have it
now--in which case the worst thing that might happen would be a free repair under warranty.