iMac Intel 21.5″ EMC 2638 Teardown

Duration: 45 minutes

Steps: 8 Steps

This iMac looks nearly identical to the last one—just a few tweaks here and there. What’s changed? Maybe a bit of power, maybe a new connector to keep things interesting. We’re about to dive in and see what’s really going on under the hood of this updated 21.5″ model. Feeling like you need something bigger? Don’t miss our teardown of the new 27″ version, too. For the latest repair adventures, step-by-step guides, and behind-the-scenes peeks, find us on Twitter, Instagram, or Facebook.

Step 1

– Updated Specs:
Apple continues to use that tricky foam adhesive to keep the display in place—no surprise there. Luckily, we’ve got some tips to help you tackle that sticky situation if it comes up.
It’s a bit disappointing that Apple hasn’t made any changes to the iMac’s display cable, which remains delicate and easy to damage. So, when you’re opening it up, just take your time and handle with care.
2.7 GHz quad-core Intel Core i5
Iris Pro graphics
802.11ac Wi-Fi
PCIe flash SSD available
With careful cuts and patience, you’ll be able to get inside and work on it.

Step 2

Our standard 21.5″ iMac now comes with an open PCIe SSD slot, making it easy for DIYers to upgrade and save some cash. Ready to give your machine a boost? Follow along, and if you hit a tricky spot, you can always schedule a repair.

– We had to dig in and pull out the logic board from the iMac. Not exactly our idea of a good time—work is work—but hey, totally worth it in the end.

– This is a nice surprise compared to last year, when the low-end 21.5’s logic board greeted us with empty solder pads and dashed hopes.

Step 3

– This section highlights the BCM94360CD, a Broadcom AirPort card that supports the latest 802.11ac Wi-Fi standard, bringing faster wireless connections to your device. Curious about what’s inside? Well, we anticipated seeing hardware similar to that in the refreshed MacBook Airs from earlier this year, since they’re both updated with the new ac standard. Specifically, you’ll find the Broadcom BCM4360KML1G 5G Wi-Fi 3-stream 802.11ac gigabit transceiver—it’s the same chip that powers the ac Wi-Fi in the 11″ and 13″ MacBook Air models. Additionally, there are three Skyworks SE5516 modules that handle dual-band 802.11a/b/g/n/ac WLAN front-end functions, and a Broadcom BCM20702 single-chip Bluetooth 4.0 HCI solution supporting Bluetooth Low Energy (BLE). If you need help or encounter any issues, you can always schedule a repair.

Step 4

– Let’s take a peek at the familiar faces on the front-side IC lineup, with a little shakeup in the CPU/GPU department:

– Under the hood: a 2.7 GHz quad-core Intel Core i5, working in tandem with Intel Iris Pro graphics.

– Intel E213B384 keeps everything in sync as the platform controller hub.

– Texas Instruments Stellaris LM4FS1AH steps up as the microcontroller.

– Broadcom BCM57765A1KMLG takes care of gigabit ethernet and handles the SDXC card reader duties.

– National Semiconductor VM22AC is also hanging out on the board.

Step 5

– Recognize those front-side chips? Let’s check out the party happening on the back:

– Intel DSL3510L Cactus Ridge Thunderbolt controller

– Analog Devices SSM3302 audio amplifier

– Vimicro VC0359 webcam processor

– Intersil ISL6364 multi-phase PWM controller

– Cirrus Logic 4206BCNZ audio controller—yep, the same one from last year’s 21.5-inch model

Step 6

– It looks like Apple managed to kill two birds with one stone — if hard drive cables were birds. The SATA power and data cables for the hard drive come bundled together, making upgrades a little simpler and saving a step or two. Follow these steps to disconnect and replace the cables as needed. If you need help, you can always schedule a repair.

Step 7

We lined up this new heat sink next to last November’s chunky, spider-like unit, and couldn’t help but notice how much sleeker it’s gotten. What gives? How did they slim it down so much?

Looks like this is the first aluminum iMac with a CPU that’s soldered right to the board—a quiet but definite move that makes upgrading your iMac even trickier.

– Apple’s design team has slimmed down the CPU heat sink, making it look slicker than ever.

– Heads up: the CPU is locked in place—soldered right onto the logic board—so swapping it out or upgrading isn’t on the menu.

– 21.5-inch model fans, good news: the 2.9GHz Core i5 CPU is upgrade-friendly, and those double-sided sticky strips from the 2012 model work perfectly here too.

Step 8

– iMac 21.5″ EMC 2638 Repairability Score: 2 out of 10 (with 10 being a total breeze).

– Yes, you can swap out the RAM and hard drive—but only after a lot of sticky tape wrangling.

– On the bright side, budget-conscious folks can now add a second hard drive to the base iMac, thanks to the return of the Fusion Drive connector on the logic board.

– Heads up: the CPU is soldered right onto the logic board, so upgrading or replacing it isn’t happening.

– The glass and LCD are now fused together, and the magnets are gone—so the old pop-off trick won’t work here.

– Pretty much everything you might want to replace (like RAM) is tucked behind the logic board, so you’ll be doing a major teardown to get to them.

– To seal everything back up, you’ll need to carefully remove the old double-sided tape and apply new tape to restore that fresh-out-of-the-box look. If this sounds like a lot, you can always schedule a repair.