Just to be clear: I flashed the firmware on the graphics card which, like I said, is pretty risky. Flashing the motherboard BIOS (another MSI tech support suggestion) wouldn't have helped since I already did that earlier this year, and since this motherboard is several years old it was the newest version. More importantly, nothing else on the motherboard was malfunctioning in any way.
Fortunately, if you have a Vega 64, it's most likely still under warranty.
Thanks for your help.
This particular MSI tech told me to
1. Reinstall Windows with a fresh install. (I used Windows Reset)
2. Flash the motherboard BIOS/UEFI
3. Contact AMD or Microsoft.
I shouldn't have listened.
I just remembered I had flashed the RX 460 firmware earlier when it wasn't having any problems, so I went back to a previous version. It's been several days, and I still haven't gotten around to reinstalling all my apps and reconfiguring my windows settings.
Again, thanks for the info.
Thank you so much for encouraging me to flash the BIOS!
I've spent last 2 days trying to solve CODE 43 issue using internet advisory on my new MSI RX 560 4 GB BIOS card - with no success.
What worked was to flash the VBIOS
Let me describe details. My config is:
After software updates I'm using the newest drivers:
With all above I've still got the error code 43. What I did was:
1. Download ATI Flash
2. Make a current BIOS backup
3. Update the BIOS to the only present & validated I found:
Here it is! After restart everything started to work as it was supposed to be from the beggining.