Most standard TX9 Pro units are powered by the Octa-core CPU. However, some newer "Pro" versions or clones may use different chipsets like the Allwinner H616 or different WiFi modules (LP6330 vs. RTL8723BS).

This is the most comprehensive archive. Search for "TX9 Pro" to find various versions, including the stock Android 7.1 Marshmallow or newer 9.0 builds.

Once you have located a link and downloaded the .img file, you generally have two ways to flash it: