Here are some of my OC results, to give you and idea :
- 1075mhz / 5-5-5-10 / 2.1 vdimm
- 1100mhz / 5-5-5-12 / 2.2 vdimm
- 1116mhz + / 5-5-5-12 / 2.25 vdimm
Also, you could invest in a ram cooler, like the Corsair Dominator Airflow.. it's worth the peace of mind, and is more easily installed than the OCZ XTC cooler IMO. Works great !