iMac Screen Overheated and Black Spot Formed on LCD

[ksb43]

Hey this really freaked me out. Hopefully no major damage has occured to my system. I use my iMac at work so it stays on all day. It already gets insanely hot on it's own, but this afternoon the sun was shining on it through the window and all the sudden I noticed a big black oval spot on the left side of the LCD screen. Kind of like the weird spots you see on broken LCD screens. As soon as I lowered the shades it started to fade. I turned the computer off immediately, so hopefully when I turn it back on the spot is completely gone. Anyone have this happen before? What's inside the iMac on the left side, is it the graphics card? Processor? The iMac's are very poorly designed and overheat to the point where you can't even touch them without burning your hand.

Kevin

 

[patrick0brien]

-ksb43

The black spot is what happens when the LCD gets too hot and can't react to the electrical field anymore - no permanent damage.

I am concerned about your temperature. Is there any way you could measure? "burned my hand" is a bit relative - even with a "Human-typical" pain threshold of 130deg F.

If it's getting that hot - I'd say your machine has an issue.

 

[ksb43]

Well that's a relief.

I don't mean like instant third degree burns. I mean you can't comfortably keep your hand on the machine for more than 5 seconds. But I have an iMac at home that feels the same way. I get that the aluminum is supposed to draw the heat away from the hardware, but I don't think any consumer product should ever get that hot. I feel like at the very least it increases the chance that the graphics card, motherboard, etc will be damaged by overheat ing, but I dont know that much about hardware so I could be wrong.

 

[patrick0brien]

-ksb43

Well, aluminum is a fairly decent heat conductor. I think you are correct that the aluminum is being used for heat dissipation from the iMac's screen. I wouldn't know as I don't have a recent one yet. I can however vouch that the AppleTV gets to about 125deg, that's getting close. But it's supposed to.

 

[ksb43]

Installed iStat. Feeling the top, the imac is not too hot to touch right now:

HD: 130
CPU A: 108
Airport Card: 139
Ambient: 76
GPU: 128
GPU Diode: 130
GPU Heatsink 126
HD Bay 1 126

Temps in Fahrenheit.

There are times when it is significantly hotter however. I'll try to catch one of those times and post the temperatures then. What's with the airport card being so hot?

 

[patrick0brien]

-ksb43

Those ranges seem to be pretty normal. However, if you feel your ventilation isn't good enough you can get Fan Control to goose the settings a bit.

I find it more robust than smcFanControl and like it very much on my MacPro and Mini.

The Mini is a home server and is never off, also sitting on an entertainment center shelf so I goose it a little bit. the MacPro has full racks of RAM that is notoriously finicky with temp, so I goose that slightly as well.

 

[ksb43]

Does that program allow you to create rules that tell it to say always run the fan 20% faster than it thinks it needs to be or do you have to manually set the RPMs?

 

[maccam]

Yep thats normal,

I can hardly hold my hand on the top of my Dads iMac (aluminum).