How much storage do the black Apple TV models contain? Can it be upgraded?

Officially, the black Apple TV 2nd Gen and Apple TV 3rd Gen have no internal storage.

However, iFixit tore apart the 2nd Gen model and discovered that it has 8 GB of flash RAM to act as a buffer during streaming. A curious member of the XBMC forums was the first to teardown the 3rd Gen model and determine that it has 8 MB of flash RAM, too. Although this existing flash RAM cannot be upgraded, iFixit also noted that there is space to accommodate an additional onboard memory module of the same size.

Consequently, it appears that Apple designed the Apple TV 2nd Gen and Apple TV 3rd Gen models either to make it simple for the company to ship future models with additional internal storage, although it did not, or perhaps the company may have once intended to ship these Apple TV models with more internal storage -- for applications, perhaps -- but decided against it prior to shipping.

The Apple TV 4th Gen, Apple TV 4K, and Apple TV 4K (2nd Gen), which also are black, are -- or were -- available with either 32 GB or 64 GB of internal flash storage. They cannot be upgraded after purchase.

Also see: What type of hard drive does the original Apple TV use? Can it be upgraded?

What type of processor do the black Apple TV models use? Can it be upgraded?

Apple officially only notes the processor type for the black Apple TV 2nd Gen model -- an Apple A4. However, iFixit confirmed that the Apple A4 processor in the second generation Apple TV has a maximum clockspeed of 1 GHz.

Likewise, for the Apple TV 3rd Gen, Apple only specifies a single core Apple A5 processor. A curious member of the XBMC forums was the first to teardown the Apple TV 3rd Gen and discover that its Apple A5 processor also runs at 1 GHz. Interestingly, further analysis by Chipworks determined that this 32 nm Apple A5 (APL2498) processor actually has dual cores, but only one is activated or operational.

For the Apple TV 4th Gen, Apple specifies a dual core Apple A8 processor, but not its clockspeed. Third-party software evaluation has determined that it runs at 1.4 GHz. Specifically, it is a 20 nm proccessor (APL1011) manufactured by TSMC.

For the Apple TV 4K, Apple specifies that it has an Apple A10X Fusion processor just like the iPad Pro models from the time of its release. Like the applicable iPad Pro models, the Apple A10X Fusion processor in the Apple TV 4K runs a 2.3 GHz, has three cores, a 64-bit architecture, and an embedded M10 motion coprocessor.

Finally, for the Apple TV 4K (2nd Gen), Apple states that it has an Apple A12 Bionic processor with a 64-bit architecture and an unspecified clockspeed. However, third-party analysis has determined that the A12 Bionic processor runs at 2.49 GHz.

The processor in each black Apple TV model cannot be upgraded.

Also see: What type of processor and video processor does the original Apple TV use? Can either processor be upgraded?

How much RAM of what type do the black Apple TV models support? Can it be upgraded?

The Apple TV 2nd Gen has 256 MB of RAM integrated with the Apple A4 processor and the Apple TV 3rd Gen has 512 MB of RAM integrated with its Apple A5 processor.

The Apple TV 4th Gen has 2 GB of RAM onboard and cannot be upgraded.

Finally, as first discovered by developer Steve Troughton-Smith, the Apple TV 4K has 3 GB of onboard RAM.

The RAM cannot be upgraded in any black Apple TV models.

Also see: How much RAM of what type does the original Apple TV support? How do you upgrade it?