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RRmalvado

macrumors 6502
Original poster
May 27, 2010
352
25
I have an older iMac (MA589LL) that I recently upgraded to 4GB and Snow Leopard which is running beautifully. I do have an issue with it though, and it's been occurring for a while:

Whenever the machine goes to sleep and I wake it up, the monitor turns on just fine but after about 5 seconds it goes back to sleep. I have to repeat this about 3 times and then it is fine.

It's an annoying issue but not a deal breaker as I can just turn it off. I searched for sleep issues/turn off issues and have not found anything.

Any ideas here?

NOTE: Issue occurred before the upgrades. I've also tried resetting the PRAM and NVRAM. I have also used different keyboards/mouses.
 
Try an archive and install and see if that helps. Do you have a hot corner set to sleep?
 
Try an archive and install and see if that helps. Do you have a hot corner set to sleep?

No hot corners setup and have reinstalled Snow Leopard.
For giggles I even tried other OSes : WinXP, Vista, Win7, Ubuntu and they exhibit the same issue.
 
So from my research, it is definitely a power supply or logic board issue.

Has anyone here experienced something similar regarding this? Or can offer any input?
 
No hot corners setup and have reinstalled Snow Leopard.
For giggles I even tried other OSes : WinXP, Vista, Win7, Ubuntu and they exhibit the same issue.

If it happens with other OSs (via Boot Camp, not Parallels or Fusion), then it's definitely a hardware issue.
 
If it happens with other OSs (via Boot Camp, not Parallels or Fusion), then it's definitely a hardware issue.

Definitely agree. Could it be the inverter?

I don't think it's the power supply because the machine itself remains on (evident by programs continuing running, it locks if i set it to lock, downloads keep downloading).
 
so is it going back to sleep or is the display shutting off? Maybe try an external display if available.

I originally thought it was going to sleep since it would lock but when i disabled that function it stayed on the desktop (or at whatever program i have running), so the display seems to be having the actual issue.

How can I connect an external display onto this iMac?
 
I had this on my older iMac. Basically it wakes, then immediately goes dark, but I can still run the computer blind. I just basically figured it was due for a restart.
 
I had this on my older iMac. Basically it wakes, then immediately goes dark, but I can still run the computer blind. I just basically figured it was due for a restart.

How'd you fix it? Or am I misinterpreting
 
Ok, well using an external monitor the computer is 100% usable.
I even tried using Logmein.com and I could remote in just fine and use the iMac.

So there is something definitely wrong with the LCD.

Based on this is there something I can try to fix myself? Could it be the power supply? or the inverter or __________?
 
Just in case anyone has the same issue, I resolved it by using a new keyboard and mouse.

I'm guessing the Apple Keyboard/Mouse combo (the one it came with) was shorting out the iMac? That's the only sensible explanation I could think of.

All in all, it's fixed and I can continue on with my projects.
 
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