Nuno Mfa :
Specs :
MoBo : Asus M5A97 LE R2.0
GPU : R7 260X
PSU : Corsair CX series CX 600 80 PLUS Bronze
CPU : FX6300
and i want to pute two GeForce GTX 780 6008 MHz , and don't worry about budget!
Well Your current CPU would need overclocking to eliminate as much bottleneck as possible, or you would have to look at grabbing an FX 8120 and overclocking it, or a FX 8350. The FX 8350 should be overclocked as well for the same reasons, but if you leave it at stock it will bottleneck less than your current CPU or the FX 8120.
In order to do SLI GTX780 and overclock your CPU, you would be looking at a good 850w power supply and maybe an aftermarket CPU cooler. Here is a few good PSUs that would suit your needs well:
http://www.ncixus.com/products/?sku=94404&vpn=220%2DG2%...
http://www.ncixus.com/products/?sku=78945&vpn=P1%2D850B...
http://www.ncixus.com/products/?sku=38650&vpn=CP%2D9020...
These are all very high quality units, and are all Gold certified. The first one is the cheapest and has the best Warranty