DDR2 OR DDR3 AHHH!! >=[

Well either way i'd be spending the same
with the 780i i;d be spending the rest on corsair dominator ram
which is like 5-5-5-15 and 1066hz
with the 790i i'd be getting the ocz ddr3 ram which is 7-7-7-20 and at 1333hz i think
unless theirs a better option of ram for the DDR3

HELP Appreciated, thank you!

Ram doesn't generally limit system, only if you have not enough of it. (GB) (not DDR2 vs DDR3) hard drives = good limit to what you do, I'd personally go with DDR2, DDR3 = showoff to say LOOK WHAT I GOT!!

790i still has issues...
780i is pretty solid these days...
i dont see how you would be spending the same with the 790i...the board is more expensive... and the ddr3 1333 will still be more expensive than a 4gb 1066 mhz 5-5-5-15 ddr2 kit.

Those timings on the 1066 MHz DDR2 are not that great, just get some good quality 800 MHz RAM and OC it (even better get one with low timings (4-4-4-12?)).

780i (less so) and 790i are both terrible. Do yourself a favor and just skip both of them altogether.

Unless you overclock your CPU past FSB1600 (400) you don't need DDR2-1066 RAM.

Look at ATI 4870 video cards, the X2 coming out in August takes the GTX280 to task. As far as motherboard look at X48 boards with DDR2-800.

FYI: Corsair Dominator RAM is garbage. You can do much better for less elsewhere.

DDR3 has higher available bandwidth.
DDR2 mostly tops out @ PC2 8500 (with some special OC sets up to PC2 9600)
DDR3 starts out @ PC3 8500 (DDR3 1066) bandwidth and you can get PC3 10600 (DDR3 1333), 12800 (DDR3 1600), 14400 (DDR3 1800) and 16000 (DDR3 2000) bandwidth ratings. You end up with higher latency for that bandwidth though.
PC2 8500 @ CL5 will be faster than PC3 8500 @ CL7.
Prices on DDR3 have dropped pretty fast DDR2 and DDR3 prices
Of course if you have a lot of RAM bandwidth you have to remember the other end of the FSB where the CPU will usually have less bandwidth. It doesnt really give you any significant advantage if the bus is wide at one end and narrow on the other end.

DDR3 is better suited to the Nehalem motherboards where the front side bus is done away with in favor of QuickPath and memory controller on the CPU instead of the Northbridge, and the RAM is setup in 3 banks instead of two.
The current X48 1600FSB has a theoretical bandwidth of ~12GB/s and QuickPath X58 motherboard will be a bit more than double that theoretical bandwidth.