Gigabyte GA970A ud3p
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128651
The best am3+ board under $100.
750Ti & 260x are pretty much equal in performance, I'd say buy whichever is cheaper.
The CX430 would be sufficient for your system.
Idle temps aren't really important.
Load temps is what you should monitor.
Download HWInfo
http://www.hwinfo.com/
Max Package(core) temps - 70C
Max Socket(CPU/motherboard) temps - 80C
You should know that Idle amd core temps are usually inaccurate until they hit around 40C.
If you really want...
I personally wouldn't recommend Raidmax Cobra
http://www.hardocp.com/article/2014/03/18/raidmax_cobra_power_500w_supply_review/9#.VKEbhP9CU
Have a look at the Power supply tier list & go for a better quality unit.
http://www.tomshardware.com/forum/id-1804779/power-supply-unit-tier-list.html...
Either board would work just fine.
Since its a budget build, I'd say go for whichever is cheaper.
As for the psu, the Raidmax Cobra is not good.
How much power your system will need, depends on your gpu.
which gpu are you planning to run?
Unless you plan on running 5ghz 24/7, the fx8350 would be the better choice.
Not that the 8350 won't do 5ghz, the 9590 is higher binned, meaning it has higher chance of hitting 5ghz stable with lower vcore.