Overclocking the AMD 64 FX-51

I'd had some luck overclocking the FX-51 (from 2200 - 2400) and am looking
for others who have done so. I am using an ASUSTek SK8N motherboard with 2
Gig of memory. I would like to know what core voltage you have had the best
results with. I have not been able to maintain 2400 for extended periods
due to temperature issues, but I can run at 2300 indefinitely . I don't have
any special cooling devices installed, only CPU fan and several case fans.
In addition the environment where the computer is located can get warm. I'm
especially looking for optimal core voltage settings.

Thanks for any info you can offer,
Gregory I. Hayes