Switched the dip switch to use the backup bios ?
Removed power + batrt and reset bios jumper ?
not sure if the AM4 versions have the option to hold down power button for 15 seconds to kick back to the 2nd bios- unless you were already using this method
guessing you've pulled CMOS bat out aswell? might help might not but least you've covered all the steps
Yup, thanks for the suggestions folks, tried all options at this point. I can get it to boot into backup BIOS providing I switch from dual to single BIOS with the dip switch. I'm unable to flash the main BIOS into a working state and the backup BIOS will not allow me to select any sort of boot drive.
I read somewhere it does not have Xmp profiles that's why I asked in a previous post.
Did you overclock anything before you started having the issues?
Yeah, it's funny because I've seen the option in the BIOS on multiple times (and used it and it worked, it's how I got my memory happily running at 2933Mhz!) but it's hit and miss whether it's there or not. This points to a dodgy BIOS flash of some kind.
I'm RMA'ing it and going for the MSI X370 Carbon instead. I simply cannot recommend this board, even if it worked well the BIOS and utilities are just so so poor, imho. I've not seen such crud from a mobo manufacturer for a fair while.