According to Apple,
"The SMC Update fine tunes the speed and operation of the internal fan."Apple released this update because owners have been complaining of overheating issues with Macbook Airs. This thread on their discussion forum, has over 3,000 views and over 50 replies.
My MBA would freeze up and then unfreeze and then freeze again, at an interval of about 10 to 15 seconds. This happens when I watch video on iTune, QuickTime or even those flash based videos such as YouTube.Despite the update, many are still complaining, either saying their systems didn't need the update or that the update didn't improve things. For example, this post says:
CPU monitor shows one core shutting down itself when this happens, and the other core would run at 100% (roughly half for user and half for system). When the system try to take 100% of the single core left, the OS would freeze.
I suspect this is an overheating problem, but I have no prove. All heat monitors indicate temperatures in acceptable range, but I suspect a particular unmonitored component may have overheated causing on CPU core to shut down.
The SMC Update didn't worked for me: it said my machine was already up to date. And my fan were running on 6200 rpm all the time.Theories are that the issue really lies in the OS, as the post posits:
This behaviour leads me to something we all already knew: Adobe Flash Player is a cpu hog, no doubt there. However, the problem is with exhibition of graphics, which grows so much that forces the SMC cut the power on one of the cpu cores.
So this is my theory:Some have wondered if the increased popularity of Apple produced has produced quality control issues. Of late, we have seen reported nano explosions, keyboard freeze issues on MacBooks, problems with defective DVD as well as BSODs during installation of Leopard - and on and on.
When the heat reaches a certain limit, instead of lowering the frequencies, it disables one core and we have the intermittent freezing problem.
In fact I tried using windows xp through boot camp and no matter what I did, it never freezed.
My opinion is that the problem is OS and/or driver related and I think it will be fixed in the future with a patch.
The unusual design of the MBA surely places more stress on the components, heat-wise. Much as owners probably will hate to admit it, it's not designed to be a desktop replacement and certainly not a gaming laptop - you're just asking for overheating.
It's obvious, though, that however the MBA is programmed to respond to overheating - it ain't working for many users, and correction is still called for.
