Yeah AMD really fucked up with the 390X/390 this time around.
Teardown's reveal it's actually the exact same as the 290X, and all the 'performance' came in the form of drivers which people found out by forcing a 390X driver onto the 290X and it turned out to be exactly like the 390X.
Even funnier is that the 290X is a copy of the even older Radeon 7970 core (which is like 3-4 years old now)
And so they're somehow expecting people will buy a $400 card that's basically using 4 year old tech.
Also didn't know OP already bought the 970, right on with that then.