Hi Mako. Yeah, in the Uk when I ordered my iMac there was no option to add AppleCare because it already had 3 years being an educational purchase. And with the noise it spins up a second later then you can hear a fairly loud humming noise but then after it randomly stops making the humming noise, not immediately but maybe an hour later or 30 mins later and when it does it goes dead quiet, how I'm sure it should be. It is really noticeable. For instance the past hour it's been dead silent, then I changed my background picture and it started off again. And with the screen I saw in the "Yellow Tinge Testing" thread a picture of an iMac with no tinging on the right and one with a consistent yellow on the left and the difference is astounding. This iMac (my 3rd) really looks more like the one on the left and my 2nd one I had before looked like the one on the right.
When I turned it on this morning I was fairly sure there was slight yellow tinging on the right hand side anyway in a vertical line and I wasn't sure if I was imagining things so I asked my Mum to take a look and I said nothing to affect her judgement and she also thought that a) it was not as good as the 2nd and b) slight yellow tinging on where I said.
So I was fairly sure that the screen on this one was not as good as the 2nd one. And because this one made the same humming sound I thought that maybe I had been stupid and that the 2nd one was fine. That is why I have come here for advice and literally as I am typing this the humming has stopped and it's now dead silent again....
One other thing I have noticed too is that when I put the iMac to sleep after it goes to sleep it makes a sound almost like a circular saw blade coming to a stop (tic...toc...tic...toc [stop]) if you know what I mean.
It just bothers me that it seems no one else has had a problem like this yet I've had it twice. :s And I was also fairly sure that the 1st iMac I received made no noise cos I would have noticed. But that hasn't convinced me that I may have sent back a perfectly ok iMac (the 2nd) a few days ago and I've been feeling crappy all day cos of it but I shouldn't have to worry like this cos every iMac should be fine - totally disappointed with a company that I've used computers with since I was 4 and they've all been great up until now.