Advice on upgrading RAM for OC

I'm about to upgrade my RAM from 4x1GB to 4x2GB, and was thinking of upgrading to faster RAM at the same time (I am aware that only 64-bit OS's will recognize all of the RAM). While I realize that overclocking my RAM won't have a large effect on performance, it seems that my current RAM limits my comp's overclocking potential...

mobo: Intel D975xbx2
cpu: Intel Q6600 (currently at 2.66 GHz)
RAM: Transcend JetRam 4x1GB PC2-6400 (DDR2-800)

Right now I am running my CPU at 296x9=2660, and my RAM at 445 Mhz with the default multiplier (2/3). If I push my FSB (and thus, my RAM) higher, I get a failed POST. My idea would be to upgrade to 1066 Mhz Ram, and still be able to run a higher frequency with the same divider I'm using right now (2/3). My goal is to get my CPU at 356*9=3204, which would put my RAM at 535 Mhz with the (2/3) divider

In the end is it worth the extra $$ to buy the 1066 Mhz RAM?

I'm fairly new to overclocking, so if something is unclear, or I've left out important information, please let me know, and I'll do my best to help clarify.

Thank you for your time.

or u can use a lower mem multi and lower timeings which is like free speed boost.