well, people recommended that I dont put more than 2.2v for 24/7 use as long as I have good case airflow. As for the timings, core 2 duo doesnt mind higher timings and it looooves more mhz instead. I would set your timings to 5-5-5-15 and clock the memory as high as it goes with 2.1-2-2 volts. Once you have reached the highest speed your overclock allows, tighten the timings and use memtest to check for stability. Make sure you run two passes as I sometimes have a perfect first pass, then the second craps out..Good luck