O
onedog
Guest
Hi from a newcomer.
I'm really after a bit of advice or just to share my tale of woe.
I have a 17" iMac G4 1.25GHz 80GB 256Mb (USB 2.0) that was (I repeat was) working fine unitil I tinkered!
I have to stand up and admit that I've always been a PC person until recently. Not because I didn't want a Mac (I've always loved the design ethic) but just because I couldn't afford one (or perhaps I should say the one I want!). Living with PCs I've been used to getting intimate with the innards and am quite at home taking one apart and putting it back together. Not from a great technical point of view but from a sort of trained monkey, tab A into slot B sort of way.
Anyway, I bit the bullet recently and bought a Mac Mini (it's just as lovely as I thought it would be) and by coincidence picked up for free a "Blueberry" at the around the same time. I decided to upgrade the hard drive in that and add extra memory to use as a music server and backup point, all went well.
Flushed with my new found "Appleness", I picked up a 17" flat panel iMac recently, it's always been my fav iMac design. I decided that it could do with a bit of an upgrade too (1.25GHz 256Mb 80GB). I read up on all the pitfalls and advice I could find bought my ingredients (250GB HDD + 1GB Internal DDR SDRAM + 1GB External SODIMM). All appeared to go well, I remembered the thermal paste, was well grounded, watched out for cable routes etc. etc. Put it all back together, and turned it on. Nothing exciting happened, got the file with the question mark on as expected and put the 1st restore CD in. At this point I decided to zero the disk before partitoning, took a while but worked. Then I went to partition it and create 4 volumes. That started OK and then the screen went black and I heard a feint buzzing and a "Nasty burning smell !!" (see I got there in the end).
Needless to say unplugged straight away and following a couple of expletives opened up the case again. With a bit of investigation I found that the culprit was on the underside of the main logic board underneath one of the heatsink pads (one of those that needs the thermal paste) where the screw goes through to hold the base on. I've cleared away the charring! and it seems as though the support of the pad is shorting against something. It's burnt through the board but apart from that on the board the only discolouration I can find is to the black plastic insulating circle underneath, I think this is just melted from the heat of the shorting. The only things I can see it might short to are the edge of the screw hole or something else on the board but can't find any evidence of it.
Here we get to the needy part. Can anyone with some electronics knowledge explain to me why this might have occurred? and if they would have expected it to fry the main board or not? There are no other items on the board near the short and no traces that I can see so I'm wondering if it could have effected anything else? Also any idea of anything I can reinsulate the pad support with? I assume it was originally embeded in the strata of the board itself. I had thought perhaps a dob of Araldite might do the trick?
I've been racking my brain to think how I could have caused this. I did not remove the logic board at all and am very very careful about static. The only thing I could come up with is that the support of the pad was slightly longer than it should be and was almost breaking through the board itself anyway. Then with the stress of my getting into the machine, maybe flexing the board slightly? I caused the board to fail around the support leaving it open to short against the screw or screw hole surround.......well it's a theory?
Phew! that was a long post! So I'm in your hands, if anyone has any ideas, suggestions or comments (clean please (or dirty and funny)) I'd be most grateful to hear them. As for the 20" mentioned in my profile, I'm afraid I'm an addict now and I'm in negotiations for it, hence the hopefully!
Thank you all and I await your responses.
PS. Excuse any spilling mistokes but I hav to rush ov to a meating know and dont have time to chick it
I'm really after a bit of advice or just to share my tale of woe.
I have a 17" iMac G4 1.25GHz 80GB 256Mb (USB 2.0) that was (I repeat was) working fine unitil I tinkered!
I have to stand up and admit that I've always been a PC person until recently. Not because I didn't want a Mac (I've always loved the design ethic) but just because I couldn't afford one (or perhaps I should say the one I want!). Living with PCs I've been used to getting intimate with the innards and am quite at home taking one apart and putting it back together. Not from a great technical point of view but from a sort of trained monkey, tab A into slot B sort of way.
Anyway, I bit the bullet recently and bought a Mac Mini (it's just as lovely as I thought it would be) and by coincidence picked up for free a "Blueberry" at the around the same time. I decided to upgrade the hard drive in that and add extra memory to use as a music server and backup point, all went well.
Flushed with my new found "Appleness", I picked up a 17" flat panel iMac recently, it's always been my fav iMac design. I decided that it could do with a bit of an upgrade too (1.25GHz 256Mb 80GB). I read up on all the pitfalls and advice I could find bought my ingredients (250GB HDD + 1GB Internal DDR SDRAM + 1GB External SODIMM). All appeared to go well, I remembered the thermal paste, was well grounded, watched out for cable routes etc. etc. Put it all back together, and turned it on. Nothing exciting happened, got the file with the question mark on as expected and put the 1st restore CD in. At this point I decided to zero the disk before partitoning, took a while but worked. Then I went to partition it and create 4 volumes. That started OK and then the screen went black and I heard a feint buzzing and a "Nasty burning smell !!" (see I got there in the end).
Needless to say unplugged straight away and following a couple of expletives opened up the case again. With a bit of investigation I found that the culprit was on the underside of the main logic board underneath one of the heatsink pads (one of those that needs the thermal paste) where the screw goes through to hold the base on. I've cleared away the charring! and it seems as though the support of the pad is shorting against something. It's burnt through the board but apart from that on the board the only discolouration I can find is to the black plastic insulating circle underneath, I think this is just melted from the heat of the shorting. The only things I can see it might short to are the edge of the screw hole or something else on the board but can't find any evidence of it.
Here we get to the needy part. Can anyone with some electronics knowledge explain to me why this might have occurred? and if they would have expected it to fry the main board or not? There are no other items on the board near the short and no traces that I can see so I'm wondering if it could have effected anything else? Also any idea of anything I can reinsulate the pad support with? I assume it was originally embeded in the strata of the board itself. I had thought perhaps a dob of Araldite might do the trick?
I've been racking my brain to think how I could have caused this. I did not remove the logic board at all and am very very careful about static. The only thing I could come up with is that the support of the pad was slightly longer than it should be and was almost breaking through the board itself anyway. Then with the stress of my getting into the machine, maybe flexing the board slightly? I caused the board to fail around the support leaving it open to short against the screw or screw hole surround.......well it's a theory?
Phew! that was a long post! So I'm in your hands, if anyone has any ideas, suggestions or comments (clean please (or dirty and funny)) I'd be most grateful to hear them. As for the 20" mentioned in my profile, I'm afraid I'm an addict now and I'm in negotiations for it, hence the hopefully!
Thank you all and I await your responses.
PS. Excuse any spilling mistokes but I hav to rush ov to a meating know and dont have time to chick it