dont think u can oc much as ur mobo has onboard graphics and probably wont allow oc'ing. u can try resetting the motherboard jumpers to get a little bit more juice. another thing u can try is enable 'memory acceleration mode' under 'chipset configuration' in the 'advanced' menu of the bios setup. this invokes a feature of ur mother board similar to 'pat'(performance acceleration technology) availabe in higher intel chipsets like 875p.
use softwares like clockgen or bios rev, use google to get them. and see if u can change vcore or ram latency. otherwise wait for somebody better informed about the board. anyway, boards with onboard graphics have never been known for their oc'ing capabilities, whether u use agpcard or not.