What do the R9 300-Series actually consume in terms of wattage, here you go - AMD Radeon R9 390X, R9 380 And R7 370 Power consumption stress tests. : r/pcmasterrace
AMD Radeon R9 380X Performance Unveiled, 15% Faster Than The Radeon R9 380 - AMD Advises GTX 660 and GTX 760 Owners To Upgrade To Antigua XT For $229 - $249
AMD Radeon R9 380 review: The best $200 graphics card you can buy for 1080p gaming | PCWorld
Specification Radeon R9 380 GAMING 2G | MSI Global - The Leading Brand in High-end Gaming & Professional Creation