The thing is with 4GB of ram, getting over 1200 stable will be pretty difficult. I assume you are using 473 FSB x 8.5 = 4020.5 MHz?

If so, try the 5:6 divider, putting the ram speed at 1135 MHz.

Set:
Primary Ram Timings = 5-5-5-15-3-40-6-3 (leave the rest on auto)
Common Performance Level (PL) = 8
Static read Control = enabled
Dram Read Training = enabled
Ai Clock Twister = moderate
NB voltage = 1.45v
vdimm = 2.2v

Can you get that to run stable? What kind of bandwidth do you get compared to where you are at now?