I bought a new 20 inch Core Duo iMac a few months ago, my first Apple product in four years. Its clean edges look fantastic on the desk and it sits like a big brother next to my old 12 inch PowerBook G4 .
But after a few weeks (conveniently just out of the 14 day return policy) I started noticing something weird happening after waking the iMac from sleep mode. At first there was a weird flickering across the screen, the kind of flicker you get when degaussing a conventional monitor. But this seemed to last longer and longer with each sleep and eventually took over an hour to clear itself, and even longer if it had been in sleep mode overnight.
Then with the longer flicker periods I started noticing strange discolouration along the top and bottom of the screen, which didn’t fade and stayed as long as the Mac was on. The only way I found to clear the discolouration was to turn it off for a few hours which then seemed to reset the problem.
I searched the Apple forums and found a few similar cases, but nobody seemed to really know what was causing the problems. Reluctantly I decided to call Apple, but the helpdesk hadn’t heard of the problem and after testing the usual off/on hold down this and that button tricks (which I’d already tried), they suggested I take the Mac to my nearest Apple aurthorised repair centre and get it checked out.
It turns out there are three such centres close to me, all within a 40 mile radius. I rang the first (I wont name them) and they said they hadn’t heard of the problem, but if I bring it in they will take a look. Cool I thought, but when I ask how long they thought it would take to test and hopefully fix the problem, they said “three to four weeks”. Flipping heck I though, I think I’ll call one of the others. So number two, still hadn’t heard of the problem, but bring it in etc., I then ask how long, they said “two to three weeks”, so a little better than the first, but not great.
So to the third, “you will have to leave your name and number, a technician will call you back” said reception. Ok I thought, when will they call me? “within 20min” yeah right I thought! But guess what – they did, and to my surprise they had also heard of the problem, and to my surprise again – “it should only take one to two weeks max”. Brilliant – jump in the car to drop it off.
Ten days later I get a call “it’s fixed”. Cool less that two weeks – jump in the car to pick it. I’ve had it back for five days now and haven’t noticed the problem once, so it seems to have been fixed (fingers crossed). Which incidentally was just a matter of replacing the logic board, seems that there was a defective video port on it.
So if you are having similar problems with your new iMac, ring up your nearest repair centre and book it in. Apple haven’t admitted that there is a fault with the logic boards, but off the record, the technician did say he had replaced about ten boards in the last couple of months – so it may be possible that there was a bad batch of logic boards produced? Then again I just could have been unlucky!
For ref: Use the Apple Where to Buy Apple Products and Services search page to find your nearest Authorised service centre (use Find Service in the You want to: drop down, then stick in your postcode and click search).