my old Gigabyte Radeon HD 7970 $160 year ago (used). Current price about $100.
Cnebench - 87
Luxmark Open CL 3.1 ball render - 12375

from other people tests:
Nvidia GTX 1080 TI $700
Cnebench - 138
Luxmark Open CL 3.1 ball render - 23648