A29 is latest Version. No further BIOS version is released. and once update you cannot go back to older version
And re-flashing the same BIOS dont do anything.
Wait for 15 days ... Ryzen 3 is coming ... and there will be extreme competition and both Intel and AMD products will have some Price drops ... and also you will get new CPU choices
Its all Done by Windows. They ended support and removed all drivers for 8 & 8.1 so that everyone use windows 10, Same problem are with me. I cannot install Nvidia Drivers on windows 8.1
I checked your motherboard, both LAN & WAN are form Intel
LAN - https://downloadcenter.intel.com/product/82186/Intel-Ethernet-Connection-I219-V
WAN - https://downloadcenter.intel.com/download/29849/Windows-10-Wi-Fi-Drivers-for-Intel-Wireless-Adapters?product=189347
Unfortunately WIFI Drivers...
Most manufactures dont support Windows 8 now. They have deleted Drivers to make people use windows 10 only. If you dont want to go on 10. Then go to official site of Installed Lan and WAN , like Realtek, intel and download your driver from there , then install it
Where you live in India ?
Because of high custom Duty, the price is very high in India
and second thing is that Ryzen 4000 Apu are currently given to OEM only.
Wait for Zen3 Ryzen cpu launching on 8 Oct, After that old cpu prices will go down.