Is this enough to run my build

I have a fx 6300 

  • M5A78L-M LX V2
  • fx 6300 
  • 8gb ram 
  • A gtx 660 
  • antec gx700
  • 1 tb samsung hdd and 500 gb wd 
  • GE-P450N-c2 psu

can my com start up with that psu with all these components?

That power supply should be able to handle it, but I don't recommend that power supply.  It uses two smaller +12V rails which is often harder to setup and means the power supply is of relatively cheap quality.  I would recommend an XFX Core Edition 450/550w.  A Corsair CX500 would be better as well.

If you haven't bought this yet, I recommend getting a better motherboard.  With AM3+, you almost always want to go full atx.  The Asus M5A97 R2.0 is a great board.  MAKE SURE you don't get the LE version.