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Thanks Kappy,

I went to apple they said the machine was a "legacy" and that they did not service it any longer. They recommended take it in to Tekserve, who services Macs, and is recognized by apple.So I will make the trip to Manhattan this weekend. In the meantime is there anything you can tell me that will at least get me on the right track as to what kind of problem Im looking at. The mac has been a great machine since I purchased it out of the box and I would hate to have to replace it.

Loucarr

I went to tekserve and they found a "b heat sink" sensor failure in the logic board. They recommended I replace the machine as apple does not manufacture parts any longer. Im thinking of buying a logic board on eBay and trying to replace it on my own. The computer still works well and I'm reticent to give up on it. Thank you all, for your input and help. I will let you know how this all works out.

Thank you Grant. I'm handy enough to give it a go. i'll let you know how I make out.

I purchased a new logic board on eBay and was planning on replacing it, but decided to first give the machine a real good cleaning first. And see if I found any obvious problems with the "B Heatsink" sensor. While taking it apart I found that it had 3 heat sinks and not just two towers like I had seen on YouTube. The third heat sink is a funny looking thing that I can only describe as having something of a sailboat design. It sits just underneath the ram cage and the cooling coils rise up and butt up against the two main heat sinks. I must have requested that configuration when I purchased the machine from Apple. I just don't remember. That threw me off for a little while but I pressed on and removed all three heat sinks. I then cleaned and re-applied the thermal paste to the processors and heat sink connections. The sensors all looked ok so I just made sure that all the sensor connections were firmly attached, put it all back together, and said a prayer.

Thankfully the machine is now working better than ever. I haven't run the apple hardware test because I misplaced the startup disk that runs it, but I believe the problem has been solved. As soon as I find the disk I will run it. Regardless I now have a smooth quiet machine again, that I believe still has a few years left. I can't thank you both enough for you help. You put me on the right track and ultimately helped me save the machine and a significant amount of money. The machine is now operating on a 500G Solid State Drive installed with a PCI Express card and could not be quieter. I think there is lesson here on not giving up on a computer that is still viable without first making an effort to fix it.

P.S. I decided to keep the extra logic board just in case.

Thanks again

I purchased a new logic board on eBay and was planning on replacing it, but decided to first give the machine a real good cleaning first. And see if I found any obvious problems with the "B Heatsink" sensor. While taking it apart I found that it had 3 heat sinks and not just two towers like I had seen on YouTube. The third heat sink is a funny looking thing that I can only describe as having something of a sailboat design. It sits just underneath the ram cage and the cooling coils rise up and butt up against the two main heat sinks. I must have requested that configuration when I purchased the machine from Apple. I just don't remember. That threw me off for a little while but I pressed on and removed all three heat sinks. I then cleaned and re-applied the thermal paste to the processors and heat sink connections. The sensors all looked ok so I just made sure that all the sensor connections were firmly attached, put it all back together, and said a prayer.

Thankfully the machine is now working better than ever. I haven't run the apple hardware test because I misplaced the startup disk that runs it, but I believe the problem has been solved. As soon as I find the disk I will run it. Regardless I now have a smooth quiet machine again, that I believe still has a few years left. I can't thank you both enough for you help. You put me on the right track and ultimately helped me save the machine and a significant amount of money. The machine is now operating on a 500G Solid State Drive installed with a PCI Express card and could not be quieter. I think there is lesson here on not giving up on a computer that is still viable without first making an effort to fix it.

P.S. I decided to keep the extra logic board just in case.

I purchased a new logic board on eBay and was planning on replacing it, but decided to first give the machine a real good cleaning first. And see if I found any obvious problems with the "B Heatsink" sensor. While taking it apart I found that it had 3 heat sinks and not just two towers like I had seen on YouTube. The third heat sink is a funny looking thing that I can only describe as having something of a sailboat design. It sits just underneath the ram cage and the cooling coils rise up and butt up against the two main heat sinks. I must have requested that configuration when I purchased the machine from Apple. I just don't remember. That threw me off for a little while but I pressed on and removed all three heat sinks. I then cleaned and re-applied the thermal paste to the processors and heat sink connections. The sensors all looked ok so I just made sure that all the sensor connections were firmly attached, put it all back together, and said a prayer.

Thankfully the machine is now working better than ever. I haven't run the apple hardware test because I misplaced the startup disk that runs it, but I believe the problem has been solved. As soon as I find the disk I will run it. Regardless I now have a smooth quiet machine again, that I believe still has a few years left. I can't thank you both enough for you help. You put me on the right track and ultimately helped me save the machine and a significant amount of money. The machine is now operating on a 500G Solid State Drive installed with a PCI Express card and could not be quieter. I think there is lesson here on not giving up on a computer that is still viable without first making an effort to fix it.

P.S. I decided to keep the extra logic board just in case.