Confused about RAM...Asus M3A78-T (790GX+750SB)

Hi!
I'm planning to assemble a new machine for myself, curently with the following components :
AMD Phenom X3 720BE
Asus M3A78-T (790GX+750SB)
Sapphire HD 4870 512MB DDR5

Now, I'm really confused about the memory....I have two options :

OCZ 4gigs DDR3 - 1333Mhz
OCZ 4gigs DDR2 - 1066Mhz

I've tried but I'm not able to figure out whether above mentioned config, esp the motherboard would support 1333DDR3 or not.Could you please help me out on this?

In that case, what makes more sense ; going for DDR2 ram or changing the board? If the latter, could you please suggest me a board?

well if u want to get a board that allows ddr3 then u are most likely going to have to change your cpu as well... as far as i know most ddr3 boards are set up for AM3 sockets and im not sure if they are backward compatible. I would just get some DDR2 ram with good timings and u should be fine.

actually i just looked at your proc and it is an AM3 cpu so you would be ok with getting a new board if u are really wanting ddr3. but you will be looking at spending at least $300 if you are wanting a decent upgrade versus $50 for some quick ddr2 ram for the motherboard u already have...just depends on how fat your wallet is i guess

If I were you Id get the AM3 board and the DDR3 for future upgradability.
http://www.newegg.com/Product/Prod [...] 6820231180

If not going DDr3

http://www.newegg.com/Product/Prod [...] 6820231166