Dragon platform consist of Phenom II, 790GX(ddr3) , 4800 series
The 790X is consider spider platform, i think
anyways, the only differences between each of them would be the DDR3
For dragon platform you have to pay more for the motherboard and DDR3 ram
I personally think its a waste of money to go dragon platform at this stage. 890 chip set is right around the corner