Is this 750w enough?

is this good enough for a AMD FX 9590 and a AMD radeon 280x?

You wouldn't need 750W to run that. You could get the standard 550W recommendation to cover those components. 600-650 if you want lots of headroom.

I'd be more concerned with your choice of motherboard, if you want to use the FX9590

i went with this MOBO ,and i wanted to be able to add another 280x my system when ever i got the money. also, i dont think a 550w would be able to run a 220w cpu and a 280x

If you are going to crossfire soon I would bump up to a 850 watt at least . I have the Gold version of that PSU with two 7950s but only a FX-6300 cpu, that FX_9590 is going to be pretty thirsty. Quik math FX-9590=220 watt, 2x R9 280x=500watts thats 720 watts right there. 

750W is fine for a CF. if you prefer a littlebit more headroom you could switch for a 850W psu, mostly not that much more expensive.

220W TDP on the FX9590 has totaly nothing to do, with the amount of power the cpu is actualy using.  thermal design power means, the amount of heat, in Watts, that the cpu cooler should be able to dispace.

to sum everyone's comments, you would want 550w for that config, and 750w for a cf config. you most likely want to just get 1 good card instead of 2 mid high range card. consider a 290/290x




And the choice of motherboard is good for that CPU. A motherboard with a lower power phases couldn't handle it.