Max potential overclock on new hardware

[bazzard]

Hello all, I've just purchased an opti 165 and a DFI ultra D motherboard.

My question as above is how high an overclock should I expect from my system using Mach 2 cooling and the memory in my signature?

I have an enermax 460 watt power supply and will be running a 7800 GT with two optical and two hard drives.

Thanks