Hi all,
Firstly does anyone have the correct bv/schematic for this board? The one I downloaded from here has all the parts mirrored making it really difficult to test things.
We've got a bunch of old iMacs I'm trying to go through. All bar one were the single long beep so it looks like they need a ram slot reflow.
The single one that wasn't doing the long single beep it would bong you could see the light on the bottom of a usb mouse come on and the fan also comes on so it seemed like it was booting but I would get no lights on the keyboard, no caps lock. Shining a flashlight couldn't see any picture screen looks completely black so it does look like it's initialised (usually the screen would be grey if it wasn't). If you leave it on for a few minutes than hit the power button again it bongs again so it seems to be failing post and shutting off.
Took the board out and noticed the first two leds would light up but that's it. Tried power cycling it a few times and now maybe 1/10 times it gives the long 3 ram beep other times it bongs and gives the same original symptoms.
Should these boards be able to post without the GPU? I know these are a common fault so I've tried both with and without a GPU, haven't tried replacing it though as I'm struggling with space as it is so I haven't been able to tear down another one.
Doesn't seem to be a RAM fault as it is getting powered. CPUs heating up as expected so it seems all the required rails are indeed present. Haven't been able to dig through the power sequences though since the board view released seems to be mirrored, pp3v42 for instance the two resistors and cap are supposed to be on the right of the regulator according to the bv but on the board their on the left.
Thanks for the assistance.
Firstly does anyone have the correct bv/schematic for this board? The one I downloaded from here has all the parts mirrored making it really difficult to test things.
We've got a bunch of old iMacs I'm trying to go through. All bar one were the single long beep so it looks like they need a ram slot reflow.
The single one that wasn't doing the long single beep it would bong you could see the light on the bottom of a usb mouse come on and the fan also comes on so it seemed like it was booting but I would get no lights on the keyboard, no caps lock. Shining a flashlight couldn't see any picture screen looks completely black so it does look like it's initialised (usually the screen would be grey if it wasn't). If you leave it on for a few minutes than hit the power button again it bongs again so it seems to be failing post and shutting off.
Took the board out and noticed the first two leds would light up but that's it. Tried power cycling it a few times and now maybe 1/10 times it gives the long 3 ram beep other times it bongs and gives the same original symptoms.
Should these boards be able to post without the GPU? I know these are a common fault so I've tried both with and without a GPU, haven't tried replacing it though as I'm struggling with space as it is so I haven't been able to tear down another one.
Doesn't seem to be a RAM fault as it is getting powered. CPUs heating up as expected so it seems all the required rails are indeed present. Haven't been able to dig through the power sequences though since the board view released seems to be mirrored, pp3v42 for instance the two resistors and cap are supposed to be on the right of the regulator according to the bv but on the board their on the left.
Thanks for the assistance.
