RX580 is not a shitty card by any means, it's just the drivers on macOS which let it down.
I agree with u !!! The drivers r not good
Windows 10 score is much better
In fact they let it down so badly that even an ancient 4 year old card beats it by at least a healthy 37% margin (688 points @RX580 vs. 940 points @780Ti, I have my CPU OC'd at 4.2GHz as well and I had tesselation @ Extreme, yours was @ Normal)
Yo 6 cores OC to 4,2GHz + Asrock X79 Extreme6 are very strong components
I use 7700K@4,2 but with iATX Board Gigabyte Z170N-WiFi, which is not so good
Wenn I have a little bit more time for it, I'll try to bench my RX580 with Asus Z170 Sabertooth from my Music-PC.
Maybe the score will be better...
I made bench with the same settings like u, here is the difference
I did try to install 10.13, couldn't. Can't even get to the installer, crashes immediately after ACPI sleep states message. Looks like I'm stuck on 10.12 at least until 10.14 comes out, so I guess I'd better enjoy (and make do with) that Kepler performance..
I've installed 10.13 with my RX580 easily, without any issues and it works fine but I installed it on an old 2,5" HDD just to let it know if it works. I think, it's nonsense to make any benchmark with this old HDD.
When I install 10.13 on SSD, I'll give u the benchmark feedback immediately.
P.S. Question to all owners of RX 580: guys, should we sell our strong and beautiful graphic card