What to replace my R9-290 ?

Hello hardware experts,

I  have a Sapphire Tri-X R9 290 OC, I would like to replace it, for my budget I've seen the R9 290X or the R9 390.

R9 390 is newer, use less electricity, but has less shading units.

I would like to have :
- faster crack speed
- same or less noise than my current (that's why I don't consider R9 290X2 for example)

What would you advice me ?

Thanks a lot.