iFixit has done a robust teardown of the iMac Pro, and we finally have a complete picture of which components can be upgraded and how easily. Additionally, the teardown found an impressively large cooling system responsible for the silent running we experienced when we saw the iMac Pro up close last month.

As we noted then, the Fusion Drive setup with a standard desktop hard drive from the standard 5K iMac is gone, as is the hatch that allowed upgrading the RAM. These changes and others have made room for a massive, dual-fan cooling system that Apple says offers 80 percent greater cooling capacity than we saw on the existing 5K iMac. There's also a bigger air vent on the back of the machine (see our earlier gallery below for a glimpse at that). Thanks to all this, the machine runs very quietly and is not warm to the touch, except right around the vent.



Samuel Axon

Samuel Axon

Samuel Axon

Samuel Axon

Samuel Axon

Samuel Axon

Samuel Axon

Samuel Axon

Losing that service hatch is only part of the problem with upgradeability on the iMac Pro, though. Not only do you have to open the casing completely to access any components, but iFixit found that the components that can be upgraded are all "buried behind the logic board, requiring a lot of disassembly for access."

If you're willing to brave it, you can replace the RAM, which comes in your usual 288-pin DDR4 ECC RAM sticks—nothing fishy or custom there. iFixit successfully installed different RAM with no problems. Unfortunately, the base model comes in a configuration of four 8GB sticks for a total of 32GB, so you'll have to pull 8GB out to put any more in. That's common for machines like this. The CPU is socketed. However, the existing chip is custom; it's designated Intel Xeon W-2140B, which iFixit speculates is an underclocked W-2145. Because it's a custom chip, a successful replacement with another chip may not be a sure thing, but it might be possible.

It's a similar situation with storage. The base model iMac Pro has dual 512GB SSDs, but they're custom, so upgrade potential is uncertain. There is one thing you can be certain about: you can't upgrade the Radeon Pro Vega 56 GPU. It's soldered onto the logic board. However, it was clear to us when Apple first demoed the iMac Pro that external GPUs connected via Thunderbolt 3 are the intended solution.

On the bright side, Apple changed some small things around the logic board, making getting at the components a little easier than before.

iFixit also found a 500W power supply and confirmed our earlier suspicions that nothing is different about the display. It's the same 5K display seen in the standard iMac—in this specific case, it's LG model LM270QQ1. Other than maybe dreaming of OLED and a hypothetical real HDR standard for computer monitors, though, nobody was complaining about the existing display anyway.