https://www.newegg.ca/tools/power-supply-calculator
The 50 series cards are pretty efficient and don't have the transient spikes issue of the 30 series. You can get away with having a lower wattage PSU that is closer to your actual requirement instead of 40-50% headroom that used to be suggested.
Ran into this issue recently. Saw a random post on the other site about it being a wine bug. That led me down the path of trying older versions of wine and that solved the problem.
Grab the last version of wine 9 from https://github.com/Kron4ek/Wine-Builds and run the installer from the directory where wine 9 was unpacked.
./wine /path/to/game/installer
Hopefully it'll get fixed soon in wine 10 but given the nature of the bug, that could take a while.