A System-on-a-Chip (SoC) is the heart of most mobile devices. The three main Chinese manufacturers of non-Intel ARM-based Android TV box SoC circuits are Allwinner, AMLogic and Rockchip. An SoC is sometimes also erroneously referred to as a chipset.
Allwinner is the black sheep among these manufacturers because of a past history of benchmark cheating and incompatibility with KODI (XBMC) software, the most common media center software used on Android TV boxes. I tend to avoid Allwinner.
Rockchip was the favored SoC maker back in 2013 when the first low-cost Android 4.0 TV boxes started becoming popular. My early 2013 Smallart UHost2/Probox2 stick from Geekbuying used a 32-bit Rockchip RK3066.
AMLogic’s lower priced 64-bit S905 SoC is the new popular favorite for Android TV boxes. AMLogic has also gained favor with KODI developers. My 2016 Mini M8S from Gearbest featured pre-rooted Android 5.1.1 and it has been rock solid stable in operation.
I was not lucky with the new Mini M8S II (AMLogic S905X), also from Gearbest (Android 6.0.1). A “root” method is not yet available and it has significant firmware flaws, e.g., the ENTER key is inexplicably disabled on external USB and RF keyboards. Despite that, unlike the stability horrors I had with the “highly regarded” 2013 ProBox2, the Mini M8S II is still stable in actual use. By 2016 standards, the 2013 ProBox2 would be considered pure garbage for many reasons.
TV box manufacturers add their own support chips and firmware to these SoC chips. Sometimes the firmware used on one TV box may also work (more or less) on another TV box with the same SoC. However, often this will not work, especially if they use different support chips, e.g., wi-fi.
Firmware from one type of SoC will not work on a different type of SoC, even the closely related AMLogic S905 and S905X. Flashing firmware intended for one SoC to a different type of SoC will likely “brick” your TV box converting it into a novelty paperweight.