I was able to recover my iMac 27" graphic card by open the computer and applying an electronic Contact Cleaner (I used M500 from BASTON.com.br), but there are many brands out there. I really didn't disconnected any inside cable, I just carefully pull up the display for at least to be able to see inside, since there are short and fragilely connected cables. I've followed ifix.com repair guide for this repair, but I didn't make all steps, again, I've just removed the eight T10 Torx screws securing the LCD to the outer case (to remove these screws I've used a standard screwdriver, without any trouble, despite the magnets attracting the tool and the screws. To put the screws back, I've needed to use two screwdrivers to position the screw correctly). Then, after shaking the product, I've applied the Contact Cleaner a lot, from both sides, and from the top. Again a lot, quite 1/4 of the product. Then, I left the computer alone for 20min. And finally, it has worked as it was new. Of course, ALL THIS SIMPLE PROCESS YOU NEED TO DO WITH THE ELECTRICITY CABEL DISCONNECTED. These cleaners are inflammable.
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I was able to recover my iMac 27" graphic card by open the computer and applying an electronic Contact Cleaner (I used M500 from BASTON.com.br), but there are many brands out there. I really didn't disconnected any inside cable, I just carefully pull up the display for at least to be able to see inside, since there are short and fragilely connected cables. I've followed ifix.com repair guide for this repair, but I didn't make all steps, again, I've just removed the eight T10 Torx screws securing the LCD to the outer case (to remove these screws I've used a standard screwdriver, without any trouble, despite the magnets attracting the tool and the screws. To put the screws back, I've needed to use two screwdrivers to position the screw correctly). Then, after shaking the product, I've applied the Contact Cleaner, from both sides, and from the top. Then, I left the computer alone for 20min. And finally, it has worked as it was new. Of course, ALL THIS SIMPLE PROCESS YOU NEED TO DO WITH THE ELECTRICITY CABEL DISCONNECTED. These cleaners are inflammable.
So, I didn't need to replace the graphic card, so I don't know if the cleaner has fixed some soldering connection, or if it was the dusty problem. Really, it has a lot of dusty inside, I have this iMac since 2009. But, really I din't cleaned it up properly, since I was afraid to disconnect the cables. I just applied the Cleaner, and it is working fine now. I reboot the imac again and again, and it boots perfectly now.
I was able to recover my iMac 27" graphic card by open the computer and applying an electronic Contact Cleaner (I used M500 from BASTON.com.br), but there are many marks out there. I really didn't disconnected any inside cable, I just carefully pull up the display for at least to be able to see inside, since there are short and fragilely connected cables. I've followed ifix.com repair guide for this repair, but I didn't make all steps, again, I've just removed the eight T10 Torx screws securing the LCD to the outer case (to remove these screws I've used a standard screwdriver, without any trouble, despite the magnets attracting the tool and the screws. To put the screws back, I've needed to use two screwdrivers to position the screw correctly). Then, after shaking the product, I've applied the Contact Cleaner a lot, from both sides, and from the top. Again a lot, quite 1/4 of the product. Then, I left the computer alone for 20min. And finally, it has worked as it was new. Of course, ALL THIS SIMPLE PROCESS YOU NEED TO DO WITH THE ELECTRICITY CABEL DISCONNECTED. These cleaners are inflammable.
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I was able to recover my iMac 27" graphic card by open the computer and applying an electronic Contact Cleaner (I used M500 from BASTON.com.br), but there are many brands out there. I really didn't disconnected any inside cable, I just carefully pull up the display for at least to be able to see inside, since there are short and fragilely connected cables. I've followed ifix.com repair guide for this repair, but I didn't make all steps, again, I've just removed the eight T10 Torx screws securing the LCD to the outer case (to remove these screws I've used a standard screwdriver, without any trouble, despite the magnets attracting the tool and the screws. To put the screws back, I've needed to use two screwdrivers to position the screw correctly). Then, after shaking the product, I've applied the Contact Cleaner a lot, from both sides, and from the top. Again a lot, quite 1/4 of the product. Then, I left the computer alone for 20min. And finally, it has worked as it was new. Of course, ALL THIS SIMPLE PROCESS YOU NEED TO DO WITH THE ELECTRICITY CABEL DISCONNECTED. These cleaners are inflammable.
So, I didn't need to replace the graphic card, so I don't know if the cleaner has fixed some soldering connection, or if it was the dusty problem. Really, it has a lot of dusty inside, I have this iMac since 2009. But, really I din't cleaned it up properly, since I was afraid to disconnect the cables. I just applied the Cleaner, and it is working fine now. I reboot the imac again and again, and it boots perfectly now.
MY SOLUTION (working):
I was able to recover my iMac 27" graphic card by open the computer and applying an electronic Contact Cleaner (I used M500 from BASTON.com.br), but there are many marks out there. I really didn't disconnected any inside cable, I just carefully pull up the display for at least to be able to see inside, since there are short and fragilely connected cables. I've followed ifix.com repair guide for this repair, but I didn't make all steps, again, I've just removed the eight T10 Torx screws securing the LCD to the outer case (to remove these screws I've used a standard screwdriver, without any trouble, despite the magnets attracting the tool and the screws. To put the screws back, I've needed to use two screwdrivers to position the screw correctly). Then, after shaking the product, I've applied the Contact Cleaner a lot, from both sides, and from the top. Again a lot, quite 1/4 of the product. Then, I left the computer alone for 20min. And finally, it has worked as it was new. Of course, ALL THIS SIMPLE PROCESS YOU NEED TO DO WITH THE ELECTRICITY CABEL DISCONNECTED. These cleaners are inflammable.
So, I didn't need to replace the graphic card, so I don't know if the cleaner has fixed some soldering connection, or if it was the dusty problem. Really, it has a lot of dusty inside, I have this iMac since 2009. But, really I din't cleaned it up properly, since I was afraid to disconnect the cables. I just applied the Cleaner, and it is working fine now. I reboot the imac again and again, and it boots perfectly now.