|"And I haven't orderd my motherboard yet"|
Why would you order the RAM before you ordered the board??
"I have AMD ll X4 965"
Which means a Phenom II X4 965 Deneb Black Edition. It's a 125W (possibly 140W) CPU so make sure you have a damn good power supply.
"I'm confused; it lists higher support from 1666mhz and 1800mhz at overclocked memory but it doesn't list 1600? Can someone clarify on this"
The Phenom II only officially supports up to DDR3-1333. You can run higher rated RAM, but testing has shown that DDR3-1333 generally scales the best.
Did you download the motherboard manual or check out the memory compatibility list? You can run DDR3-1600 at it's rated speed but you *may* have to manually configure the memory settings in the BIOS. RAM that's rated higher than DDR3-1600 will automatically underclock. See chart: