Aha! The "Apple part number" from step 11 is a great clue! Searching for these cards by this part number yields many online sellers.
There were three cards that could go in this model:
* NVIDIA GT120 (256Mb): part #661-4991
* NVIDIA GT130 (512Mb): part #661-4990
* ATI Radeon HD 4850 (512Mb): part #661-5135
The ATI card is generally marginally cheaper than the equivalent NVIDIA.
I found the adhesive (or fit) quite strong. Pushing on the bottom part of the glass created a small gap at the top, which I could fit a craft knife (xacto blade) into. This made it easier to carefully lever the glass out for me.
The display can actually be pulled out slightly further than it initially seems. When you gently pull it up, you'll experience some resistance, which I initially thought indicated it was as far as it could go. But an extra bit of (still very gentle) force can pull it up a few more millimetres, which means the opening tool can fit.
Also, it seemed to me to actually be helpful to lever the cable out of its port before removing the ribbon from the adhesive on the plate, since this allowed better access to the adhesive with the opening tool.
I found using the opening tool to wedge up (toward the case) from between the metal bit (which is a plate) and the dock socket was the easiest way to do this.
I found I had to gently pry the retainer open with a craft knife (xacto knife?) as the plastic opener tool was too blunt or soft to get any purchase...
Any tips for selecting a replacement gfx card? How can I be sure my purchase will work?
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