We got similar setups, Im just running DDR3 instead of DDR2. Its a great board to overclock with, ive gotten to 545MHz FSB before and run 500 as a daily overclock. But for it to be 100% stable the CPU vcore sits at like 1.44. But im watercooled so it's all good, and been stable for over a year at these settings.
3.4GHz should be no problem for you. Up your CPU voltage to around 1.35 (max i recommend if your running air cooling is 1.4V) and your looking at a FSB of 425 with your CPU multiplier at 8X for 3.4GHz. Also, if you run in to stability problems, try turning off LLC (load line calibration) These boards do not seem to like LLC and a heavy overclock for some strange reason...
Also, CPU-Z Validation for 545 FSB