Make sure that all plastic was removed from the PCH fan, some come with a lot of shiny plastics and they're covered in film.
This post has a bios mod that adds pch fan control among other things: https://www.hardwareluxx.de/community/f219/asus-x570-strix-series-x570-e-gaming-x570-f-gaming-x570-i-gaming-1236042.html
Edit: also heard this software allows control but I'm unable to verify https://github.com/LibreHardwareMonitor/LibreHardwareMonitor, give it a try,
yes soyo h81 is compatible with r9 290. below is the lowest price on Amazon, LGA1150 socket, X58 intel chipset. https://www.amazon.com/INTEL-Motherboard-LGA2011-CROSSFIRE-USB3-0/dp/B06WWHJHT4/ref=sr_1_1?s=pc&ie=UTF8&qid=1488156900&sr=1-1&keywords=X79+MOTHERBOARD+beyang