Late 2009 iMac 27" Video Card Repair — 4850 — 2nd Bake

Video shows my 2nd bake of the video card. My 1st bake lasted only 4 months (due to thermal paste used, I think), and that video (showing complete motherboard removal) is here: https://youtu.be/v1DXBLkiqFM My iFixit Guide is here: https://bit.ly/2nCnNan If your bake is successful, please register your "Completion" on my iFixit Guide page by scrolling down to the "Conclusion" box and then clicking on the blue "Give the author +30 points!" button. You'll need an iFixit account to do that, but it's free and easy. ? TOOLS to open/close the iMac: • Torx T10 (T9 works, but T10 is best): https://amzn.to/2UjzuFB • 2 strong suction cups (for front glass removal): https://amzn.to/2tkcmvJ • Philips #1 "+" screw driver (for RAM door): https://amzn.to/38VWOgK • Anti-static wrist band (connect wire to earth ground): https://amzn.to/2uSTy74 ? OTHER ITEMS needed: • Thermal Paste -- I used K4 Pro (for the GPU chip) and K5 Pro (for memory chips -- K5 Pro is a thermal pad replacement). They are NOT electrically conductive and come in this kit: https://amzn.to/38WkEZO • ISO Alcohol 99% (just as good as the Anhydrous Ethanol I used): https://amzn.to/2GFZRNY • Swabs & Tissues • Dust blower - Giottos Rocket Blaster Large: https://amzn.to/2OgHHXt • Microfiber cloth (for cleaning the screen/glass) • Flashlight (to peer into the dark spaces inside the iMac) • Aluminum Foil (make feet to raise up video card in oven) • An oven set to 200°C/400°F (without which this repair is in vain) • Time & Patience ► I used a Samsung EVO 850 1TB SSD to replace the stock Apple hard drive, but the 860 EVO or Crucial MX500 are equivalent. To use an SSD in late 2009 27" iMac, you'll also need a special mounting bracket and a separate temperature sensor: • Bracket: https://amzn.to/37Zn4qg • Sensor: https://amzn.to/3b3knWU • EVO 860 (1TB): https://amzn.to/2RKem9M • Crucial MX500 (1TB): https://amzn.to/2tkaq6r ? NOTE: I added Amazon Affiliate links above on Feb.1, 2020. Your price is the same even if you don't use my links, but if you do kindly purchase via my links, a small commission would be paid to me by Amazon which helps to support this Channel. ?? IF NEEDED: Replacement ribbon cables from AliExpress (CHINA): BIG: http://bit.ly/2AdHvCV SMALL: http://bit.ly/2zRDbIC ? 4850 Card Photos (cleaned): TOP: https://flic.kr/p/RjLLCd BTM: https://flic.kr/p/RjLKGf ♨️ This was the 2nd time I baked this Radeon 4850 video card at 200°C (400°F), and this time I baked it for 10 minutes. My 1st bake was for 9 minutes and it lasted 4 months, even with a fan-control app used to set all 3 fans to 1800rpm. Symptoms: it wouldn't boot fully and would freeze at the Apple logo screen with the progress bar only 50% finished, sometimes with screen artifacts. At times when it would boot to the desktop, there were artifacts that made using the computer impossible. I think the failure of my 1st bake was due to my bad thermal paste job, not the baking time. Clean off ALL old paste and only apply new thermal paste. ‼️ BE CAREFUL WHEN REMOVING CONNECTORS! On Oct.13, 2018, someone attempting the bake said he accidentally ripped off a connector from the logic board. That connector is shown at 44:20 to 44:34 in my video above and is one of the first connectors you must disconnect when removing the display. To avoid such accidents, please slowly remove all connectors and use very little force. If something seems stuck, it could be a locked connector like that one, where you must squeeze the tabs on the sides of the connector to unlock it and then slowly pull to remove it. ? Fan Control Apps to keep your iMac running cooler (I'm using both on different Macs and can therefore recommend either): • Macs Fan Control: https://www.crystalidea.com/macs-fan-control • smcFanControl: https://www.eidac.de ? I'm not the only one who has gotten 2+ years of use after a video card bake. Mr. Tak Engle used my video as a guide and baked his mid-2011 iMac's video card once in Jan. 2018. I chatted with him in Jan. 2020 and he confirmed his iMac was still working fine 2 years later. The amazing part is he accidentally dropped it from off a bed onto a concrete floor during his disassembly, but the iMac still worked! His bake video is here: https://youtu.be/3Txgc-ECNdw ?? UPDATE: Feb. 10, 2020 — Still going strong after 2 years and 7 months! See my video update here: https://youtu.be/HBxpFwKcbK8 ?SUPPORT THIS CHANNEL If you wish to buy me a drink or otherwise support my content creation: https://www.paypal.me/supportJDW ? Please SUBSCRIBE: http://www.youtube.com/c/JDW11/?sub_confirmation=1 #Apple #Macintosh #iMac #VideoCard #JDW