Apple delivered the first M1 iMac models to customers last Friday and started selling them in its own stores. iFixit has now taken a look at the circuit boards of the device and published a corresponding teardown.
iFixit disassembled the purple mid-range iMac model with an 8-core CPU, an 8-core GPU, and 8GB of RAM. Side note: This version is different inside than the base model, which was equipped with a 7-core GPU. This is because of two different cooling systems. The base iMac has a single fan and a heatsink while the higher-end models with 8-core GPU have two fans and a heatpipe along with heatsinks. The teardown starts with a detailed X-ray image.

There are two main metal plates inside and an RF pass-through for the antenna hardware in the Apple logo. The iMac is sealed with what iFixit calls "classic iMac glue," which isn't as sticky and difficult to work with as the glue Apple uses on products like the iPad.
M1 iMac 24″: More details to follow
Because the front of the iMac is a single piece of glass, there is no separate chin panel blocking access to the innards, as in previous models. The chin houses the logic board. There are two fans blowing inward. A copper heat pipe and two short heat sinks dissipate heat from the M1.

iFixit has detailed the components on the logic board, including SK Hynix memory, Kioxia NAND flash storage, and an Apple-designed M1 SoC, Bluetooth/WiFi module, and power management IC, among other components. There is a "mystery button" with three LEDs underneath, which iFixit says will be revealed later. iFixit also plans to provide details on the Magic Keyboard's Touch ID sensor, info on the speakers, and a repairability assessment. (Image: iFixit)