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Veltliner · Jun 9, 2009, 06:18 PM

This happens every two, three weeks:

I put my 24" white iMac, Tiger, to sleep, and punch a key to wake him up: nothing. Continues to doze.

I can only switch off the computer by pressing the on-button on the back for a few seconds, and then start it up.

Is this very unusual? (I just ran DiscWarrior for a wacom tablet problem, which solved it. But this one remains).

Veltliner · Jun 9, 2009, 11:45 PM

Well, it just happened again.

Twice in one day now.

Lots of software and files open, and I had to shut off the mac with the power button.

Big Mac · Jun 10, 2009, 03:07 AM

Every so often, in some hardware generations, some people will report chronic wake from sleep problems. It used to be a much more prominent problem during the G4 era. It's not something I've heard of in recent times, and I wouldn't settle for it if it were happening to me. I would insist on repair or replacement. If you wish, you can try an SMU reset or something similar, but I doubt that will help. When did you get the iMac, and when did you first notice the problem?

Veltliner · Jun 10, 2009, 05:28 AM

I got it in September 2007.

The original Apple warranty is over, but I can still get a repair through my credit card's buyer protection (which doubles the manufacturer's warranty).

What might be the problem here? That little chip that's supposed to be reset with an SMU reset. (Sure I did it, but who knows if it helps?).

Big Mac · Jun 10, 2009, 06:29 AM

I really wish I could give you a cause. It's a rare malady for modern Macs, AFAIK.

I've always wondered how generous credit card extended warranties would be. I think it's worth looking into. Failing to wake from sleep is especially difficult to diagnose because there's no log written about what happened.

Veltliner · Jun 10, 2009, 11:33 PM

I have until September.

If it only happens every two weeks (I do the put to sleep/wake him up-game quite often), then I won't worry.

I have the slight suspiction that the reason is Capture One 4.1.1. I have to use this older version, as newer versions don't run on Tiger (I'm going to upgrade to Snow Leopard).

Capture One also slows down the computer sometimes, if too many applications are open (Photoshop, Bridge, Capture One, Text Wrangler, Browsers). I restart, and then it's alright again.