I have the same setup with your first one (waiting for a Phenom II), except the OCZ's (i have mushkin's 4GB 1066) and i am running @1066 this moment :

http://valid.canardpc.com/show_oc.php?id=455611

Bios was set at 800MHz, and then due to HT oc, i got this result...

Now for your new X3 8750BE i suggest you set the ram voltage to the default (see what the product page for the OCZ reapers say) and try...If you like post your bios settings here so other people can help you with your settings...

Hope it works for you...

Cheers...