Hi John, This sounds intriguing--and like you say, what do I have to lose. Although I have worked with Macs for many years, I do not have much experience inside one. Are there photos or videos for the process you describe? I am not even sure what you mean when you say "Take the card off of the heat sink." And where do I buy the paste? Thanks for your help! -Joe
On Friday, March 30, 2018 at 3:00:36 PM UTC-6, John Carmonne wrote: > > > On Mar 30, 2018, at 10:53 AM, Jim Scott wrote: > > > > > In the case of your 2008 iMac, in addition to all of the above, the > cooling fins of the heat sink can be clogged by dust, etc. over time as the > air intake vents directly below the card and heat sink assembly are > hoovering up stuff from the desktop. This leads to overheating and eventual > failure of the BGA. Reflowing the BGA doesn’t work because by the time the > problem shows itself, too many of the microscopic traces inside the chip > have been damaged by arcing. That’s why a more permanent repair involves > replacing the chip with a new one. But new chips are hard if not impossible > to find, and my favorite eBay bad chip repair/replace guy refuses to work > on those old iMac video cards because he can’t guarantee a reflow and he > can’t obtain new chips that will work with the card. > > > > Been there, done that a number of times. It’s time to ewaste that iMac, > in my experience. > > > > Jim Scott, Eureka, CA > > > > I have recently fixed a number of these iMacs may sound crazy but it > worked for me. It's free and at this point you have nothing to lose. > > Take the card off the heat sink and clean all the paste off. > Pre heat oven to 390 F (pre heat is important) > Place card on 4 small aluminum foil balls at the corners > Bake for 7 mins > Open door and let board cool don't touch it or move it. > When cool reinstall (don't forget to apply new paste). > > I have also found some with faulty fans so check the fan working before > you put it all back together. > > > > John Carmonne > Yorba Linda CA > 92886 USA > MacPro 2.66 Quad Nehalem > > > > > > > -- You received this message because you are a member of the iMac Group, a group for those using Apple iMacs and eMacs. The list FAQ is at http://lowendmac.com/imac/list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/imaclist --- You received this message because you are subscribed to the Google Groups "iMac Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
