Help with dead iMac

[brian.grossman]

Guys,

I really need help with some diagnostics on my iMac (late 2009 27" iMac)I'm about to the point of taking it in to a professional, but I'd like to get some thoughts on what may be the problem. When I attempt to power it on, it makes the chime, and then the screen may or may not light up. If it has been several days since I messed with it, it may go ahead and boot up and work for 2-3 minutes and then the screen goes black and its done. Once you have powered it on recently, then the next time you do it, the screen won't even light up (but it always chimes). I have removed the ram and tried it one stick at a time, and that doesn't have any effect. Am I looking at a bad motherboard, or perhaps the processor? Any thoughts?

Thanks for the help,

Brian Grossman

 

[ryguy92000]

Black Screen puts me in the Red...

So it would seem you have a dying LCD. Which IS fixable by the DIYer. Its tricky as the cables are small but that would indeed be my diagnosis. IF you are able try plugging into an external and if the external display stays steady on then you may be out an LCD.

Good Luck!

 

[ssls6]

Guys,

I really need help with some diagnostics on my iMac (late 2009 27" iMac)I'm about to the point of taking it in to a professional, but I'd like to get some thoughts on what may be the problem. When I attempt to power it on, it makes the chime, and then the screen may or may not light up. If it has been several days since I messed with it, it may go ahead and boot up and work for 2-3 minutes and then the screen goes black and its done. Once you have powered it on recently, then the next time you do it, the screen won't even light up (but it always chimes). I have removed the ram and tried it one stick at a time, and that doesn't have any effect. Am I looking at a bad motherboard, or perhaps the processor? Any thoughts?

Thanks for the help,

Brian Grossman

I would think power supply. Taking it to the apple store is a good strategy since they will properly diagnose the problem and then you can decide what action to take.

 

[havokalien]

if its not the power supply my next best guess would be the video card as it chimes, power supply would usually cause nothing to happen. Chime says motherboard is getting power at least. I have reflowed one and put new paste on it and works well now.