Macbook black screen fan running

M

macattack600

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I have a macbook with no liquid damage. Sometimes it will start up and run properly. Other times while i'm using it the screen will go black and the fan is still running but the keyboard is unresponsive like the caps lock and num lock won't light up. I have to reboot . The sleep light is broke on the bottom but the computer does sleep right. Does the ambient light sensor have anything to do with it I can see it flash when I start up the computer.
 
MacBooks don't have an ambient light sensor, unless you have one with a backlit keyboard (which is only on MacBook Pro models)
There's two items on the front right edge:
sleep light, and IR sensor port
The IR sensor is not visible, so you must be seeing the sleep light (which you said doesn't work?) It should come on briefly during boot, then turns off when the display lights up.

Your symptoms indicate likely problems on the logic board, the CPU/heatsink, and even more sound like results of liquid damage. I have seen too many to suspect anything else.
Good plan would be to remove the logic board, and inspect the underside of that logic board.
 
The whole board checks out good I took it out and cleaned it. I'm thinking it may be the logic but I'm also thinking about the Transcend memory that was put as an upgrade there is 2x1gb sticks in it. I run Techtool pro 6 and everything checks out, but I've seen memory can cause the black screen with fan running. I've stuck a hynix 512mb stick in it and held down the power button until it reset pram, now and I'm going to see what happens. If there are problems with the logic or the ram slots can it damage good ram?
 
Well I have'nt checked the transcend memory sticks but I am running this macbook with 1 hynix 512 stick and it checked out okay. So far I've used this all day and night putting it to sleep and waking up moving it around it has'nt black screened on me yet, BUT it is very slow too leopard on a duo core macbook with 512 megs of ram is not that fun. I'm thinking it's a possibility that if the os was working faster with more memory it might give me that trouble again. This macbook came with a frayed chord a horrible battery which in a good macbook if I charge it with the mac off it will knock the power from the plug and the sleep light broke and dvd refuses to read anything burned. I'm thinking there was some shorts some where but it's working better but slow. Any thoughts on it now ? Thanks.
 
My thoughts?
You need good, working memory
Leopard works better with more than 1GB - 2GB is even better.
Adding more (good) memory should normally make the Mac more stable, not less.

You keep saying that the sleep light is not working - but you now say that you see the "ambient light sensor" flash briefly at startup. The only possible light that you would see flash on the front is the sleep light, which should light up briefly at startup. If the sleep light was broken, then you should never see that work. - That light is not working as a sleep light during boot, of course, but it also tells you that it is not broken, but simply does not indicate sleep - and you say that sleep does actually work, but no light - Do I have that correct?
Do YOU have any thoughts on that?

Finally, your DVD problems are not likely related to the power problems that you might have. DVD (optical) drive problems are a typical MacBook failure. If cleaning the drive does not help (it usually doesn't, but stillworth a try), then you either replace that drive, or use an external burner.
 
Well the sleep light does not turn on ,when I close the lid the screen will shut off when I lift it back up it turns on but then shuts off till I press a key on the keyboard. I can manually put it to sleep at the apple menu too. What I was asking about the ram was when I was running 2gb I was thinking cause the processor was working faster due to any short in the board it was causing it to act funny cause the logic board was acting funny running more than one app with higher processor use. Since I have 512 in it now I was thinking because it's working slower it might not using much processor work causing any short to give me the trouble it did before. I don't see that green light at the right of the camera blink when I start it up now . Putting a different ram and holding the power button until the long beep is over and boot up what is exaclty kind of pram reset am I doing vs. cmd option p and r ? thanks.
 
That light is not ever green or any other color, but always white (when it is working).
But, must be intermittent, eh?
Your thinking is not logical :D - If your laptop was more unstable with more memory, and now more stable when you have less memory installed, then it's not the processor (or the logic board), but the memory. So, I predict that one, or both of the other memory chips is faulty. Well... - it could also be a faulty memory slot, but most likely that one slot would not work at all in that case.
Can you tell me the results after testing one chip at a time, using Memtest?

also - what is the Model Identifier (from Hardware Overview in your System Profiler?)
Is it a MacBook1,1 - or something newer?
 
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