It may not have a Retina display, but the new 21.5" iMac has some commendable specs:

• 2.7 GHz quad-core Intel Core i5 processor with 6 MB L3 cache
• 8 GB of RAM
• 1TB hard drive (5400 rpm)
• NVIDIA GeForce GT 640M graphics processor with 512 MB dedicated VRAM
• Four USB 3.0 ports and two Thunderbolt ports
• 802.11n Wi-Fi and Bluetooth 4.0

In case you haven't heard, the new iMac is really thin…kinda. At its thinnest point (around the edge), it is 5 mm thick. At its thickest, though, it is over 4 cm thick, more than 8 times the thickness of the edge.

Since the new iMac is barely thicker than a CD itself, it does not include an optical drive. However, it still does sport a plethora of ports:

• 3.5 mm headphone
• SDXC card slot
• 4x USB 3.0
• 2x Thunderbolt
• Gigabit Ethernet

We find what appear to be cooling vents on the back of the rear case hidden behind the "foot." Unlike previous revisions, the vent is rectangular instead of circular.

Even though there are vents at the bottom of the rear case, our guess is that the fan is somewhere in the middle of the iMac—where it's fattest. These slots are probably the exhaust vents that spit out air drawn in from the bottom.

Hiding above the Apple logo, we find the small dual microphone grates.

• It's listening; it's always listening…

This iMac's model and EMC numbers hide in their usual spot under the foot: A1418 and EMC 2544.

Interestingly, this iMac claims to have been assembled in the USA.

We begin to strum away at the adhesive holding the display assembly in place.

Unlike in the previous iMac, this glass is held in place with more than magnets.

To our dismay, we're forced to break out our heat gun and guitar picks to get past the adhesive holding the display down.

With the iPad-like adhesive severed, we bust out the heavy-duty stuff.

Repair faux pas alert! To save space and eliminate the gap between the glass and the pixels, Apple opted to fuse the front glass and the LCD. This means that if you want to replace one, you'll have to replace both.

• Consolation prize: repairs will no longer involve cleaning dust or fingerprints from the LCD and glass during reassembly.

The fused display may look awesome, but at what cost, Apple? At. What. Cost!?

• The cost is quickly apparent: cutting open the display destroys the foam adhesive securing it shut. Putting things back together will require peeling off and replacing all of the original adhesive, which will be a major pain for repairers.

We were fairly surprised to see that the new iMac's LCD sports the same model number as last year's—LM215WF3 from LG—even though the LCD is 5 mm thinner.

• If it's the same, why is it smaller? We surmise that Apple took all the same pieces of the LCD and crammed them into a smaller housing.

Taking a peek at the display control board reveals a couple of noteworthy ICs:

• Texas Instruments TPS65161 bias power supply
• Parade DP627HDE DisplayPort LCD timing controller

Talk about a facelift—nothing about the inside of this iMac resembles last year's model.

As we tear through this machine we'll be able to take a look at how Apple managed to eliminate a millimeter here and a micron there, one component at a time.

Here's a properly-cropped (1920x1080) version of the internals for you to use as a wallpaper. We call it the iMac 21.5" Late 2012 Wallpaper.