R9 390 mining???

[tilted]

I am trying to fill this up to see if it's worth to invest into mining : https://etherscan.io/ether-mining-calculator

How much watts does a R9 390 use?
What is the hashrate?
Should I consider buying an other R9 390? and if I do does my hash rate double? Should i upgrade my build?

Full build :


CPU: Intel - Core i5-4460 3.2GHz Quad-Core Processor
Motherboard: ASRock - H97 Anniversary ATX LGA1150 Motherboard
Memory: G.Skill - Ripjaws X Series 8GB (2 x 4GB) DDR3-1600 Memory
Storage: Samsung - 850 EVO-Series 250GB 2.5" Solid State Drive
Storage: Western Digital - Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive  
Video Card: MSI - Radeon R9 390 8GB Video Card
Power Supply: EVGA - 750W 80+ Bronze Certified Semi-Modular ATX Power Supply  ($99.08 @ DirectCanada)

[Etherion]

I sold my last R9 390. Really room heaters. 3 can hit 1kw  If your not paying for power they are great. Cheap now and fast. but if you are paying for power and your buying new I suggest going for other cards. RX470 4G if you can find. OR Nvidia 1060.

[64dimensions]

In the absence of a better choice R9 380 and R9 390 are an acceptable compromise.

These were my principal cards for a while.

The key operational premise is this, you must operate these cards to maximize hash rate per unit power.

In the case of these cards the optimal setting(s) was 800/1500. For a 6 card rig with no bios mods the power measured at the wall was around 870W with a 125 Mh/s rate. The R9 380 was about 20 - 21 and the R9 390 was about 10% higher. One card is almost $4/day and probably a 1 month ROI.