iMac Intel 21.5″ EMC 2544 Upgrade

I recently bought a late 2012 iMac with a broken screen at a very *low* price and gradually collected parts, upgrades to make this a little project machine.
Over the past weekend I used the iFixit guide to do the teardown and replace the CPU, memory, hdd to ssd, wireless card, and lcd panel. As it turns out this is a very upgradeable machine, one of Apple’s last to be clear. With a socketed CPU, I was able to take out the i5-3330s and replace it with the i7-3770s. The wireless card can be replaced with the Apple Broadcom BCM94360CD; enabling faster downloads and the feature of unlocking your mac with Apple Watch. Obviously there are huge benefits from upgrading the ram from 8 to 16GB and replacing the hard drive with solid state as well.
Having the benefit of hind site on the teardown now, there are two items I would like to have been forewarned of that could have dramatically reduced the time in repair.
- Somewhere around step 27 of the guide, when you are removing the first screws that can potentially drop down in to the “well” or bottom of the iMac, it would be good to note that you should exercise caution that these screws are “caught” or stick to the magnetized screwdriver. Reason: the bottom portion of the iMac is not only magnetized, but if you look down there, you will see a “gate” for lack of a better term. If a screw drops down there and you do not have a thin, flexible magnetized pole, you’ll have a devil of a time fishing it out.

- The second point / time saver, is when you remove the power supply. Given that we are rightly forewarned not to touch the capacitors for safety; this step can be quite sensitive. Not only are you trying to exercise caution, but the power supply is connected to the logic board in a way that you cannot see, but only feel the connector. The step reads “Squeeze the DC power cable connector tab and pull it straight out of its socket on the back of the logic board.” What you should know is the lever to be pressed down is closest to you as you remove the cable (see photo). You should also know this can be quite challenging, time consuming if you are holding the power supply with one hand and using the other to remove the cable. Ideally, someone else will hold the power supply while you stabilize the mac/logic board and remove the cable. You’ll know what I mean when you do this. I found one other video on YouTube where the person explains this but thought a photo of the connector will help:

That’s it! Other than these two points, the iFixit guide is awesome and I give it 5 stars all the way. Hope these points assist in repair if you undertake it.